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By: by Dr. F. W. Martin, Revised 1998 and 2007 by ECHO Staff
Published: 2007-01-01


How to Find the Best Plants for the Small Farm

Number and Classes of Useful Plants

TN20 Figure Title pictureIn one attempt to list all of the food plants of the world, Tanaka recorded 10,000 species in a thick volume (Tanaka,T. 1976, Tanaka’s Cyclopedia of Edible Plants of the World). Others claim that the world may contain 20,000 or even 40,000 edible plants, though these claims are not substantiated. Perhaps with the correct processing, every plant is potentially edible.

In addition to the edible plants, a very large number of plants are useful to humankind in a wide variety of other ways. Plants may serve as feed for livestock. They may also provide humankind with needed items including shelter, clothes, fibers, pipes, fishing poles, toothpicks, etc. There are also ecologically beneficial plants that protect and improve the soil and that can influence conditions such as light and wind.

Though nearly all plants are useful in some way, they are not equally valuable. For example, wheat, rice and corn may be considered the most valuable plants in the world based on the vast acreage planted to these crops, their vital role in feeding humankind, and their enormous economic value. Using various criteria, one might consider 10, 25, or even 200 species as the world’s most valuable plants. Yet, under some situations, by some people, or for some special reason, other plants produced and used on a very small scale might be precious and indispensable. The question, “Which are the most valuable plants for the small farm?”, then, becomes breathtaking.

 

The Problem of Adaptation

Adaptation as defined here is the range of environmental conditions under which a plant can survive, grow and produce. If a plant is widely adapted, it can be grown under many conditions. This is especially important when one tries to compare plants for their values. A widely-adapted plant is more valuable than one adapted to a narrow range of conditions, even if the use of the narrowly-adapted plant is of great importance. When comparing values of plants, we frequently consider their adaptation to growing conditions on small farms.

The small farms throughout the world often represent marginal areas not always well suited to agriculture. The best farming areas are frequently in the hands of a few who own or control vast acreages. There is a macrodiversity among small farms, from flat, easy-access terrain to those places where farming is very difficult such as hillsides, swamps, brushlands, extreme altitudes, rocklands and small valleys. In addition, there is a microdiversity that easily occurs within “pockets” of space with their own microclimates. This phenomenon is caused by great variability in factors such as slope, amount of soil and its nature, and the amount of rainfall, humidity, or light received. Plants respond differently to such conditions.

Now, these differences among small farms increase the problem of choosing the right plants. The problem can be seen in Central America where small farms usually produce the crop(s) necessary for their own household first, then staple foods for marketing as an income source. Often called the basic grains, these staple crops include corn, sorghum, pearl millet, rice, and beans. To this group must be added cassava and potatoes, both of great importance in many regions. The crops that are grown, and the varieties of such crops, are extremely critical, for these crops must be produced under prevailing rainfall conditions. Crops or varieties respond differently to abnormal amounts (too little or too much) and patterns (rainy season constant or intermittent; too long or too short). The problems of producing these life-sustaining crops are so great that farmers may not concern themselves with home vegetable gardens that could balance the diet for their children. On these small farms the right crops or the right varieties may differ radically from one place to another, and it is difficult to accurately predict what crop might do well in a particular location.

 

Criteria of Value as Defined Here

Because of the diversity of plants that are useful on the small farm, when thinking of their values it is useful to first classify plants by their uses. For example, in comparing plants for their values it is not reasonable to compare cereal grains to windbreaks. Therefore, all of the discussion that follows is based on the comparison of useful plants within categories as defined by the uses themselves. A very helpful list of plant uses is found as part of the Table of Contents section on the first page of this document. That list serves as an orientation to this publication.

Nevertheless, the classes of uses themselves are of different values. Judgments have been made of these values, and the categories of useful plants are listed somewhat in the order of importance in the Table of Contents. For example, food crops are listed first, and among the food crops, those great staple foods including the most important of all, cereal grains. The weakness of this classification of uses is seen in the expression, “Humankind does not live on bread alone”. Thus, in some places and under some circumstances the order of values would vary.

Within each use category, suggested criteria for deciding the value of and selecting a crop are:

  • The wideness of adaptation of the crop.
  • The quality of the crop for the use in question.
  • The useful yield for the use in question.
  • Problems in production.
  • Storage or durability.

 

Using the Tables of Useful Plants

For the avid student who wishes to learn about tropical plants and their many uses, there is never enough information. Of the hundreds of species covered by this publication, some are well known and information on them may be available in other literature. Others are inadequately known. By compiling lists of useful species and presenting them in tables, much useful information is lost, and the author apologizes. However, probably no publication can ever be adequate, for agriculture by its nature must always include local trial and learning from experience.

Information for the various categories of plants is presented in forms of generalities as text, and more specific information is given in the tables. The information in tables always includes one common name and the scientific or species name, and may include other information such as growth habitat, edible parts and uses, principal nutrients, and adaptation in terms of temperature, day length, flooding, drought, or climate region. Sometimes negative factors are mentioned. In addition, the various species are usually rated for their relative values for multiple purposes including food, animal feed, fiber, construction materials, fuel, soil amendment (soil improvement), erosion control, and climatic modification. These uses are more fully discussed in the corresponding portion of the manuscript dedicated to such crops.

 

Descriptions of Useful Plants Plants for Food: Staple Crops

Cereal and Non-Leguminous Grains

TN20 Figure 1

Figure 1. Rice (Oryza sativa) with maturing heads of grain.

Three kinds of edible seed from annual plants can be distinguished: the cereal grains from grasses, the pulses from legumes, and a miscellaneous group which, for convenience here, is called non-leguminous grains. All are annuals that are propagated from seeds.

Cereal grains are the staff of life for most of the people of the world, and wheat is number one. Rice follows, but while extremely important is low in protein. Corn has long been an important life support crop; however, as is the case with other cereal grains, it normally lacks sufficient lysine to fulfill all human dietary protein requirements. However, several high lysine corn varieties have been developed, making this crop the most important member of its class and a potentially useful lifesaver everywhere. The high protein grain triticale also has great promise. Choice of variety suited for the locale is always important for the cereals. Time of planting and harvest may also be critical.

The non-leguminous grains are an assortment of minor crops having special value in isolated regions. They should be considered as potentially valuable but experimental and only rarely could they replace a cereal grain.

On selecting a grain crop, familiarize yourself with the grain crops already grown in the region, including the varieties and their problems. Search first for improved varieties. Try to substitute high lysine (high quality protein) varieties of corn for current varieties. Then, add a little additional fertilizer to the soil and you will be repaid with generous yields. All of the grain crops in the following tables are annuals propagated from seed.

 

Table 1. A Comparison of Grain Crops

Common Name

Species Name

Growth Habit

Edible Parts and Uses

Principal Nutrients

 

Adaptation

 

Negative Factors

 

Temp.

Day-length

Flood

Dry

Amaranth

A. cruentis

 

A.

hypochondriacus

rapid, upright, branched

seed in flour,

popped

protein, starch

warm to hot

neutral

no

some

tiny seeds, some heads shatter

Barley

Hordeum vulgare

branched grass

seed in flour, cereal, malt, grits

protein, starch

cool to warm

neutral

no

no

 

Buckwheat

Fagopyrum esculentum

herabeous bush

seed in flour, cereal, green manure

protein, starch

warm

neutral

no

no

high altitude crop

Corn, Maize

Zea mays

upright grass

cereal, starches, oil, seed in flour

protein, oil, starch

warm to hot

neutral to short

no

no

 

Kañiwa Cañihua

Chenopodium pallidicaule

broadleaf herb

seed in flour

protein, starch

warm

neutral

no

some

small seeds, high altitude

Pearl Millet

Pennisetum americanum

upright grass

seed in flour,

cereal

protein, starch

warm

neutral

no

yes

 

Quinoa

Chenopodium quinoa

broadleaf herb

seed in flour

protein, starch

warm

neutral

no

some

tiny seeds, high altitude

Rice

Oryza sativa

branched grass

seed as staple food, flour, starch

starch, low protein

warm to hot

neutral

yes

no

relatively low protein

Sorghum

Sorghum bicolor

upright grass

seed as flour,

cereal

protein, starch

warm to hot

neutral

no

some

birds eat best varieites

Teff

Eragrostis tef

branched grass

seed in flour, flat bread (injera)

protein, starch

cool

neutral

no

no

small       seed, high altitude

Triticale

X Triticum aestivum

branched grass

seed as flour,

cereal, bread

starch, high protein

cool to warm

neutral

no

no

experimental, hard to get

Wheat, bread

Triticum aestivum

branched grass

seed as flour,

cereal, bread

protein, starch

warm

neutral

no

no

 

Wheat, pasta

Triticum turgidum durum

branched grass

seed as flour,

cereal, pasta

protein, starch

warm

neutral

no

no

 

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 2. Uses and Ratings (0-5) of Use for Selected Grain Crops.

Common Name

Other Food Uses

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

Modify Climate

Amaranth

edible leaves

4

2

0

0

1

1

1

0

Cañihua

edible leaves

4

3

0

0

0

1

1

0

Corn

fresh seed

5

5

0

1

2

1

1

0

Kiwicha

edible leaves

4

3

0

0

0

1

1

0

Pearl Millet

 

4

4

0

1

1

1

1

0

Quinoa

edible leaves

5

0

0

0

1

1

1

0

Rice

 

5

3

0

0

1

1

1

0

Sorghum

 

4

5

0

2

2

1

1

0

Wheat

 

5

4

0

0

1

1

1

0

Pulses (Leguminous Grains):

TN20 Figure 2

Figure 2. Pods of Pigeon Pea (Cajanus cajun), a good selection for semi-arid areas.

Pulses are the dried seeds of leguminous plants and are important as sources of protein for the diet. The same species are often useful for non-dry seeds and pods. As a group, they are limited in production per acre or hectare, but those that excel in protein content are particularly valuable. None are potentially more valuable than soybean with its high yields and content of protein and oil. But, soybean is limited in two ways: (1) it needs inoculation or to be in the presence of a specific bacterium in the soil and (2) it must mature during dry days.

For pulse crops, the appropriate variety for the locale and date of planting is extremely important, and they often have disease and/or insect problems. People often have very fixed habits with respect to these crops. Convincing them to change a variety may be very difficult. All of these crops are propagated chiefly by seeds.

Selecting an adequate pulse crop for any given region inevitably involves extensive testing of species and varieties and involving the local people in trials of suitable cooking methods that would be acceptable by the populace. The task of replacing a given pulse or introducing a new one is often quite difficult because of cultural preferences.

 

Table 3. A Comparison of Pulses (Dried Legumes Used for Cooking)

Common Name

Species Name

Annual/ Perennial

Growth Habit

Edible Parts and Uses

Principal Nutrients

 

Adaptation

 

Negative Factors

Temp.

Day-length

Flood

Dry

Bambara nut

Vigna subterranea

annual

compact, bushy herb

seeds ground or boiled, pods boiled

protein

hot

mostly neutral

no

no

hard seed

Bean, common

Phaseolus lunatus

annual

bushy herb or vine

boiled seeds, mashing and refrying

protein, starch

warm

mostly neutral

no

some

limited adaptating to the tropics

Chick pea, garbanzo

Cicer arietinum

annual

bushy herb or vine

boiled seeds

protein, starch

cool to warm

neutral

no

yes

temperate climate only

Cowpea

Vigna unguiculata

annual

bushy herb or vine

boiled seeds, immature pods, leaves

protein, vit. B

hot

mostly neutral

no

some

diseases and insects

Faba bean

Vicia faba

var. faba

annual

bush

boiled seed, roasted, ground meal

protein, starch

cool to warm

mostly neutral

no

some

Fabism (a disease) is linked to this

Horse gram

Macrotyloma

uniflorum

annual

bush or weak vine

boiled seed

protein, starch, oil

hot

mostly short day

no

some

 

Lablab

Lablab purpureus

annual

climbing vine

boiled seed, mature seeds and pods

protein, starch

warm

short day

some

some

excessive vine growth during long days

Lima bean

Phaseolus vulgaris

annual

bush or vine

boiled seed or green pod

protein, vit. B, starch

hot

variable

no

some

foliage contains HCN

Moth bean

Bigna acontifolia

annual

low trailing vine

boiled seed, ground or fried forage

protein, starch

mostly hot

neutral, short day

no

yes

difficult to

harvest

Mung bean

Vigna radiata

annual

small bush or vine

boiled and sprouted seed, edible pods

protein, starch

cool to warm

neutral, short day

no

yes

rhizobium inoculation needed in some soils

Popping bean Nuña

Phaseolus vulgaris

annual

vine

popped before eating

protein, starch

cool to warm

mostly short day

no

some

adapted to Andes Mtns.

Pea, garden

Pisum sativum

annual

weak vine

boiled seed, ground meal

protein, starch

mostly hot

mostly neutral

no

no

temperate climate only

Peanut

Arachis hupogaea

annual

small bush

dry nuts, boiled seed

oil, protein

hot

neutral, short day

no

some

diseases

Pigeon pea

Cajanus cajan

annual or weak perennial

tall bush

boiled seed, mature seed

protein

warm to hot

neutral, short day

some

some

insect susceptibility

Rice bean

Vigna umbellata

annual or weak perennial

small vine

boiled seed, edible pods, leaves

protein, starch

warm to hot

mostly short day

no

yes

poor yields

Scarlet runner bean

Phaseolus coccineus

annual or perennial

vine

boiled seed, mature seed, leaves, roots

protein, starch

cool to warm

mostly neutral

no

no

adapted to cool or temperate climate

Soybean

Glycine max

annual

mostly bushy

boiled, ground, extracted, processed

oil, high protein

hot

short day

no

some

rhizobium inoculation needed in some soils

Tarwi Tarhui Chocho

Lupinus mutabilis

annual

bush

boiled seed

oil, high protein

cool to warm

mostly neutral

no

some

seed contains poisonous alkaloids, must boil seed

Tepary bean

Phaseolus acutifolius

annual

bush or weak vine

boiled or ground seed

protein, starch

warm to hot

mostly short day

no

yes

adapted only to desert conditions

Urd bean

Vigna mungo

annual

bush

boiled or ground seed

protein, starch

very hot

neutral, short day

no

some

adapted only to dry conditions

Velvet bean

Mucuna pruriens var. utilis

annual or weak perennial

climbing or trailing vine

roased seed as coffee sub., or in tempeh

protein, oil

warm to hot

mostly short day

yes

some

seed contains poisonous alkaloids, must boil seed

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 4. Uses and Ratings (0-5) of Use for Selected Pulse Crops.

Common Name

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

Modify Climate

Bambara nut

3

2

0

0

0

1

1

0

Common bean

5

3

0

0

1

2

1

0

Cowpea

5

3

0

0

1

2

2

1

Lablab bean

4

4

0

0

0

3

3

1

Lima bean

4

0

0

0

0

2

1

1

Mat bean

3

3

0

0

0

1

1

0

Mung bean

4

2

0

0

0

1

1

0

Nuña

4

2

0

0

0

2

1

0

Peanut

5

4

0

0

0

3

2

0

Pigeon pea

4

3

0

0

1

3

2

0

Rice bean

3

1

0

0

0

1

1

0

Soybean

5

5

0

0

1

3

1

1

Tarwi

3

1

0

0

0

1

1

0

Tepary bean

3

1

0

0

0

1

1

0

Roots and Tubers:

TN20 Figure 3

Figure 3. Tubers of Jicama (Pachyrrhizus erosus),well adapted to hot, humid climate.   

Root and tuber crops throughout the world include: (1) annual, enlarged roots and tubers of little food value and (2) perennial roots and tubers high in starch. These structures are used by the plant for regrowth after an unfavorable season. Roots and tubers are widely used throughout the tropics as staple crops, and indeed are major sources of carbohydrates. Because they are limited in protein, excessive reliance upon them for food may be detrimental to health. It is difficult to pick the best because each has its advantages and disadvantages; however, cassava is the worst because of its low, poor-quality protein. Some people favor the sweet potato because it can be produced in four months, leaving the ground free for other crops. Root and tuber crops are usually widely adapted and easy to grow, but there is frequently a problem of obtaining good varieties.

 

 

 

Table 5. A Comparison Chart of Roots and Tubers

 

 

 

 

 

Edible Parts, Uses

 

 

Adaptation

 

 

Common Name

Species Name

Annual, Bi/ Perennial

Propa- gation

Growth Habit

Principal Uses

 

Temp.

Day- Length

 

Flood

 

Dry

Negative Factors

Beet

Beta vulgaris

bi, grown as annual

seed

herbaceous

roots, leaves cooked

roots- low nutrients

cool

neutral

no

no

temperate climate

Carrot

Dacus carota

bi, grown as annual

seed

herbaceous

roots, raw or cooked

high in vit. A

cool / warm

neutral

no

no

temperate climate

Cassava

Manihot esculenta

per. grown as annual

cutting

bush

tuberous root, leaf, cooked

starch

hot

short day

no

no

some var. poisonous untreated

Dasheen

Colocasia esculenta

per. grown as annual

offshoot

herbaceous

corm, cooked

starch, vit. C

hot

short day

some

no

 

Edible Canna

Canna edulis

per. grown as annual

offshoot

upright herbaceous

rhizome, cooked

starch

hot

neutral

some

no

poor quality vegetable

Jícama

Pachyrrhizus erosus

weak per. used as annual

seed

vining

tuberous root, cooked

starch, protein

hot

neutral

no

some

pods, leaf poisonous

Potato

Solanum tuberosum

per. grown as annual

tuber cutting

herbaceous

tuber, cooked

starch, vit. C

cool / warm

neutral

no

no

not tropical

Sweet Potato

Ipomea batatas var. batatas

per. grown as annual

cutting

trailing vine

vine tips &

tuberous root, cooked

starch, vit. C, maybe A

hot

mostly short day

no

no

insect problems

Tanier

Xanthosoma spp.

per. grown as annual

offshoot

herbaceous

corm, cooked

starch

hot

mostly short day

some

no

disease problems

Taro

Colocasia esculenta

per. grown as annual

offshoot

herbaceous

corm, cooked

starch, vit. C

hot

mostly short day

yes

no

needs paddy culture

Yam

Dioscorea spp.

per. grown as annual

tuber cutting

climbing vine

tuber, cooked

starch, protein

hot

mostly neutral

some

no

very seasonal

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 6. Uses and Ratings (0-5) of Use for Selected Root and Tuber Crops.

Common Name

Food Uses

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

Modify Climate

African Yam Bean

root, fresh dried seed

4

1

0

0

0

1

0

0

Ahipa

root

3

1

0

0

0

2

1

0

Arrowroot

rhizome

3

2

0

0

0

0

1

0

Cassava

root, leaves

4

4

0

1

1

0

1

0

Edible canna

corm

2

1

0

0

0

0

1

0

Potato

tuber

5

3

0

0

0

0

1

0

Sweet potato

root, leaves

5

5

0

0

0

0

2

0

Tannier

corm, leaves

5

0

0

0

0

0

1

0

Taro

corm, leaves

5

0

0

0

0

0

1

0

Yam

tuber

5

0

0

0

0

0

2

1

Yam bean

root

4

1

0

0

0

1

0

0

 

PLANTS FOR FOOD: VEGETABLE CROPS

Leguminous Vegetables:

TN20 Figure 4

Figure 4.  Winged Bean (Psophocarpus tetragonolobus) pods- may be eaten fresh when young and flexible. 

Legumes are excellent providers of at least some of most nutrients. However, they are subject to many disease and insect problems. The challenge with these crops is to find those that are well suited to a particular area and that will produce a crop throughout the year. This is a difficult, but all can be produced from seeds. Winged beans may also be propagated by tubers. Some produce a crop in winter and some in summer. Therefore, developing a selection of leguminous vegetables for a farming area requires careful trials of both species and available varieties, with attention to seasonal parameters for optimal production. Generally, several selections are desirable to assure year-round production.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 7. A Comparison of Leguminous Vegetables.

 

 

 

 

Edible Parts, Uses

 

 

Adaptation

 

 

Common Name

 

Species Name

Annual/ Perennial

Growth Habit

Principal Nutrients

 

Temp.

Day- Length

 

Flood

 

Dry

Negative Factors

Bean, Common

Phaseolus vulgaris

annual

vine or bush

pod, dry seed

general nut., starch

warm

mostly neutral

no

no

 

Chickpea, Garbanzo

Cicer arietinum

annual

bush

undried and dry seed

protein, starch

cool to warm

mostly neutral

no

some

 

Cowpea

Vigna unguiculata

annual

bush or vine

undried and dry seed

protein, starch

hot

mostly neutral

no

some

 

Faba bean

Vicia faba

annual

bush

pod, dry and undried seed

protein, starch

warm

mostly neutral

no

some

consumption related to a disease

Jack bean

Canavalia ensiformis

annual

mostly bush

small young pod

protein, starch

hot

neutral

/short day

some

no

poisonous and risky to use when older

Lablab

Lablab purpureus

weak perennial

vine or bush

dry and undried seed, pod

protein, starch

hot

short day

some

some

excessive vining in summer

Lima bean

Phaseolus lunatus

annual

vine or bush

undried seed

protein, starch

warm to hot

mostly neutral

no

no

 

Pea

Pisum sativum

annual

weak vine

pod, dry, undried seed

protein, starch

cool to warm

Neutral

no

no

strictly temperate

Peanut

Arachis hypogaea

annual

Bush

dry and undried seed

oil, high protein

hot

mostly neutral

no

some

wet seeds become poisonous

Pigeon Pea

Canjanus cajun

weak perennial

tall bush

dry and undried seed

protein, starch

hot

neutral

/short day

no

no

 

Soybean

Glycine max

annual

bush

dry and undried seed

oil, starch, high protein

warm to hot

short day

no

no

often needs rhizobium inoculant

Sword Bean

Canavalia gladiata

annual

vine

young pod

protein, starch

hot

Neutral

no

no

pods and beans may be slightly poisonous

Winged Bean

Psophocarpus tetragonolobus

weak perennial

vine

young pod, leaf, root, flower

oil, starch, high protein

hot

neutral/ short day

yes

no

 

Yardlong Bean

Vigna unguiculata ssp. sesquipedalis

annual

vine

pod

general nutrients

hot

mostly neutral

no

no

 

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 8. Uses and Ratings (0-5) of Uses for Selected Leguminous Vegetables

Common Name

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

Modify Climate

Basul

4

3

0

2

3

4

2

2

Common bean

5

3

0

0

1

2

1

0

Cowpea

5

3

0

0

1

2

2

1

Horse bean

1

3

0

0

0

2

2

1

Inga

2

2

0

2

2

2

1

1

Lablab bean

4

4

0

0

0

3

3

1

Lima bean

4

0

0

0

0

2

1

1

Mat bean

3

3

0

0

0

1

1

0

Mung bean

4

2

0

0

0

1

1

0

Paterno

2

2

0

2

3

2

2

1

Peanut

5

4

0

0

0

3

2

0

Pigeon pea

4

3

0

0

1

3

2

0

Rice bean

3

1

0

0

0

1

1

0

Soybean

5

5

0

0

1

3

1

1

Tarwi

3

1

0

0

0

1

1

0

Tepary bean

3

1

0

0

0

1

1

0

Sword bean

2

2

0

0

0

2

2

1

Winged bean

4

3

0

0

0

3

2

1

Yardlong bean

5

2

0

0

0

1

1

1

Non-Leguminous Fruit Vegetables:

TN20 Figure 5

Figure 5. Tropical Pumpkin (Cucurbita moschata) fruits.

Fruit vegetables are a miscellaneous classification that includes some produce with very excellent and some with practically no food value. There are many hundreds in the tropics, yet a relatively small number, as listed here, are proven favorites almost everywhere. Some favor the tropical pumpkin because of its high nutritive value and the many ways it can be prepared for food. The pepper and the tomato, in spite of differences in appearance and use, have much the same nutritive value. Cucumber, eggplant, melon and watermelon are interesting and entertain the palate, but they have low food value. Most are propagated by seeds, and some can also be propagated by cuttings. Except for okra, a summer vegetable, they can be produced at any time of the year. Variety is almost always important when selecting a fruit vegetable. Finding an appropriate variety may require extensive search and trial.

 

 

Table 9. A Comparison of Fruit Vegetables.

Common Name

Species Name

Annual/ Perennial

Growth Habit

Edible Parts, Uses

Principal Nutrients

 

Adaptation

 

Negative Factors

Temp.

Flood

Dry

Angled loofa

Luffa

acutangula

annual

climbing vine

young fruit

low nut. value

hot

no

no

poisonous seeds

Bitter gourd

Momordica charantia

annual

climbing vine

young fruit

vit. C

hot

no

yes

very bitter

Bottle gourd

Lagenaria siceraria

annual

climbing vine

young fruit, seed

low nut. value, seed high in oil & protein

warm / hot

no

no

low nut. value

Cucuzzi, Italian

Lagenaria siceraria

annual

climbing vine

young fruit, seed

low nut. value, seed high in oil & protein

warm / hot

no

no

low nut. value

Chayote

Sechium edulis

perennial

climbing vine

mature fruit, vine tips, roots

tips high in vitamins, minerals

warm

some

no

needs cool nights

Eggplant

Solanum melongena

weak perennial

bush

young fruit

low nut. value

warm / hot

no

some

low nut. value

Okra

Abelmoschus esculentus

annual

bush

young fruit, dried seed

fair source of most nutrients

hot

no

some

summer only

Pepper

Capsicum annuum

weak perennial

bush

young/mature fruit, leaves

vit. A & C

warm / hot

no

some

virus susceptible

Pumpkin tropical

Cucurbita moschata

weak perennial

trailing vine

young/mature fruit, seeds, vine tips

vit. A & C, seed high in oil & protein

hot

some

no

mildew

Snake gourd

Trichosanthes cucumerina

annual

climbing vine

young fruit

low nut. value

hot

no

no

poor quality

Sponge gourd

Luffa

cylindrica

annual

climbing vine

young fruit, mature sponges

low nut. value

hot

no

no

low nut. value

Tomato

Lycopersicon esculentum

annual

/ weak perennial

bush or weak vine

young/mature fruit

vit. A & C

warm

no

no

many diseases

Wax gourd

Benincasa hispida

annual

climbing vine

young fruit, seed or oil

low nut. value, seed high in oil & protein

hot

no

no

low nut. value

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 10. Uses and Rating (0-5) of Uses for Selected Tropical Fruit Vegetables.

Common Name

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

Modify Climate

Bitter gourd

3

0

0

0

0

0

1

0

Chayote

2

1

0

0

0

0

2

1

Melon

3

1

0

0

0

0

1

0

Okra

4

1

0

0

2

0

1

0

Pepper

5

0

0

0

0

0

0

0

Pumpkin

5

3

0

0

0

0

1

1

Tomato

4

0

0

0

0

0

0

0

Leafy Vegetables:

TN20 Figure 6

Figure 6. Highly nutritious leaves of Drumstick (Moringa oleifera) tree.  Source: Tim Motis.

As a rule, leaves have high value as food, especially the dark green leaves, but always contain too much fiber and often contain various antinutrients such as oxalic acid. Leaves as a part of the diet can eliminate blindness in children caused by a lack of sufficient vitamin A in their diet. There are many leafy vegetables to choose from. A good rule is to vary them in the diet. A half-cup of cooked leaves every day is a good amount to consume.

Most of the typical tropical leafy vegetables do not have varietal names, but all of them are highly adapted to tropical conditions.

 

 

 

 

 

 

 

 

Table 11. A Comparison of Leafy Vegetables.

 

 

 

 

 

Edible Parts, Uses

 

 

 

Adaptation

 

 

Common Name

 

Species Name

Annual/ Perennial

Propa- gation

Growth Habit

Relative

Yield

Relative

Quality

 

Temp.

Day- length

 

Flood

 

Dry

Negative Factors

Amaranth

Amaranthus gangeticus,

A. tricolor A. hypochondriacus

annual

seed

herb

leaf, whole plant, cooked

high

high

hot

mostly short day

no

some

short life span, insects

Belembe

Xanthosoma brasiliense

perennial

off-

shoot

herb

leaf and stem, cooked

low

very high

hot

neutral

yes

no

low production

Bok choi

Brassica rapa subsp. chinensisis

annual

seed

herb

leaf, head, raw or cooked

med

med

cool to warm

neutral

no

no

 

Bush okra

Corchous olitorius

annual

seed

herb

leaf and hoot, cooked

high

med

hot

neutral

no

some

weedy

Cassava

Manihot esculenta

perennial

cutting

bush

leaf and shoot, cooked

med

med

hot

neutral

no

some

needs cooking or is toxic

Chaya

Cnidoscolus chayamansa

perennial

cutting

bush

leaf and shoot, cooked

very high

high

warm to hot

neutral

some

some

somewhat toxic

False roselle

Hibiscus acetosella

weak perennial

seed

bush

leaf and shoot, cooked

med

med

warm to hot

short day

no

some

weedy nature

Horseradish tree

Moringa oleifera

perennial

seed, cutting

tree

leaf, young fruit, flower, root

very high

high

hot

neutral

no

some

too vigorous

Indian lettuce

Lactuca Indica

annual

seed, cutting

tall herb

leaf, raw

high

high

warm to hot

short day no

no

very tall

 

Kai choi

Brassica juncea

annual

seed

herb

leaf, head, raw or cooked

med

high

warm

neutral

no

no

 

Kale, Ethiopian

Brassica carinata

annual

seed

herb

leaf, raw or cooked

high

med

warm

neutral

no

no

 

Katuk

Sauropus androgynus

perennial

seed, cutting

bush

shoot, cooked

med

high

hot

neutral

no

no

 

Lagos spinach

Celosia argentea

annual

seed

herb

leaf and shoot, cooked

high

med

hot

short day

no

no

weedy

Lettuce

Lactuca sativa

annual

seed

herb

leaf, head, raw

medium

medium

cool to warm

short day

no

no

 

Spinach, Malabar

Basella rubra

perennial

seed, cutting

climbing vine

leaf and shoot, cooked

high

low

hot

short day

no

no

fruits during short days

Spinach,

pacific

Abelmoschus manihot

perennial

cutting

tall bush

leaf and shoot, cooked

high

medium

hot

short day

no

no

slimy when cooked

Spinach, water

Ipomea aquatica

perennial

cutting seed

trailing vine

leaf and shoot, cooked

high

low

warm to hot

short day

yes

no

weedy in canals

Sweet potato

Ipomea batatas

perennial

cutting

trailing vine

shoot, cooked

medium

medium

hot

short day

no

no

weevils

Table 12. Uses and Ratings (0-5) of Uses for Selected Leafy Vegetables.

Common Name

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

Modify Climate

Amaranth

5

1

0

0

1

0

0

0

Belembe

5

1

0

0

0

0

0

0

Cassava

5

5

0

1

1

0

1

0

Ceylon spinach

4

0

0

0

0

0

1

1

Chaya

4

1

0

0

0

0

1

0

Horseradish tree

5

3

0

0

1

1

2

2

Indian lettuce

4

3

0

0

0

0

0

0

Indian mustard

5

4

0

0

0

0

0

0

Kangkong

5

3

0

0

0

0

1

1

Katuk

5

2

0

1

0

1

1

0

Leucaena

4

4

0

2

4

4

3

2

Okinawa spinach

3

2

0

0

0

1

2

0

Pacific spinach

5

2

0

0

0

1

1

0

Lagos spinach

4

0

0

0

0

1

1

0

Sissoo spinach

3

0

0

0

0

1

3

0

Sweet Potato

5

5

0

0

0

0

3

0

Watercress

5

3

0

0

0

0

0

0

Miscellaneous Vegetables:

TN20 Figure 7

Figure 7. Egusi Melon (Citrullus lanatus) fruit

Some of the very best of the tropical vegetables do not conveniently fit into any other category. The edible part is highly variable, and production is often inefficient (however, water chestnut is very highly productive). Most of these species are perennials. Almost all are of high quality. Taken as a group, they are highly valuable, gourmet species. Few of these vegetables have selected varieties.

Many are easy to grow and successful almost everywhere. They are all worth trying where space permits. In some cases, the production technology and markets for these crops has already been developed.

 

 

 

 

Table 13. A Comparison of Miscellaneous Vegetables.

Common Name

Species Name

Annual/ Perennial

Propa- gation

Growth Habit

Edible Parts, Uses

Principal Nutrients

 

Adaptation

 

Negative Factors

Temp.

Day- Length

Flood

Dry

Asparagus

Asparagus

officinale

perennial

seed

offshoot

bush, large rhizomes

young tender shoots, cooked Pickled

vit. C

cool to warm

neutral

no

some

 

Buffalo

gourd

Cucurbita foetidissima

perennial

seed

bush / vine

seed for oil

and flour

oil, high protein

warm to hot

 

no

yes

 

Bunching onion

Allium

fisulosum

perennial

seed

offshoot

herb with bulb

entire plant as condiment

vit. C

cool to warm

short day

no

no

 

Chinese chives

Allium tuberosum

perennial

offshoot

herb

green foliage as spinach

vit. A & C

warm to hot

short day

no

no

 

Coconut sprout

Cocos nucifera

perennial

seed

tall tree

root ball after germination

 

hot

neutral

some

some

 

Egusi

Citrullus lanatus

annual

seed

trailing vine

roasted seed as snack or ground

high protein

warm to hot

 

no

yes

 

Izote

Yucca spp.

perennial

seed cutting

large woody bush

mature bud and flower raw or cooked, heart must be cooked

flower-vit. C, heart- calcium

warm to hot

neutral

no

no

chiefly for other uses, inefficient production

Onion

Allium cepa

perennial

seed bulbs

herb

bulb as a condiment

vit. C

warm

short day no

no

specific varieties & planting dates

Pitpit

Setaria palmifolia

perennial

cutting

large grass

bottled

up flower cooked as vegetable

protein

hot

short day

some

no

inefficient

production

Rhubarb

Rheum rhaponti

annual in tropics

seed

offshoot

large herb

petioles cooked

vit. C

cool to warm

neutral

some

no

mostly temperate

Roselle

Hibiscus

sabdariffa

annual

seed

large woody herb

calyxes of pod as fruit

vit. C

warm

short day no

some

 

 

Sweet Corn

Zea mays

annual

seed

tall herb

immature ear

carbo- hydrate, P, niacin

warm

short day to neutral

no

no

 

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 14. Uses and Ratings (0-5) of Uses for Miscellaneous Vegetables.

Common Name

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

Modify Climate

Bamboo

3

2

0

4

3

0

4

4

Coconut sprout

5

4

3

4

2

2

4

4

Izote

2

1

1

0

0

0

1

0

Pacaya

3

0

0

0

0

0

1

0

Palm hearts

3

1

1

3

2

2

1

1

Pitpit

2

2

0

0

0

1

2

0

Sweet corn

4

2

0

1

1

0

1

0

Water chestnut

4

0

0

0

0

0

0

0

Plants for Food: Fruit and Nut Crops

Basic Survival Fruits:

TN20 Figure 8

Figure 8. Fruit of a FHIA (Honduran Foundation for Agricultural Research) banana (Musa spp.) variety with resistance to the fungal disease, Black Sigatoka.

The banana, plantain, breadfruit, and coconut are basic survival foods with much in common with the root and tuber crops. However, they are high in carbohydrates and low in protein. These crops can be grown on most farms in the tropics. They produce a lot of food for the efforts necessary to grow them. They might be seasonal, however, and by themselves they are not a complete diet. It is very difficult to add even one more species to this short, valuable list. These fruits probably occur already in every region where climate and soils permit. If not, they need introduction. These common fruits are often unappreciated for their fine qualities.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 15. A Comparison of Basic Survival Fruits.

Common Name

Species Name

Propagation

Growth Habit

Edible Parts, Uses

Principal Nutrients

Adaptation

Temp.

Flood

Dry

Banana/ Plantain

Musa spp.

offshoots

large herb

fruit, raw, cooked

starch

hot

some

little

Breadfruit

Artocarpus altilis

root cuttings

med. tree

fruit cooked

starch

hot

some

some

Coconut

Cocos nucifera

seeds

tall palm

fruit, many uses

protein, oil

hot

some

some

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 16. Uses and Ratings (0-5) of Uses for Basic Survival Fruits.

Common Name

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

Modify Climate

Banana

5

4

1

1

0

1

1

1

Plantain

4

3

0

0

0

0

2

0

Breadfruit

4

3

0

1

1

1

2

2

Coconut

5

4

3

4

2

2

4

4

High Value Fruits:

TN20 Figure 9

Figure 9. Atemoya (Annona cherimola X A. squamosa), a delicious dessert fruit. Source: Tim Motis

The tropics are rich in highly varied, delicious and nutritive fruits. Of the hundreds that exist, only a few of the most superb and easy-to-grow (e.g. prickly pear) fruits are listed here. Fruits that are high in nutritive value, easy to grow, and versatile in their use will be especially beneficial on the small farm.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 17. A Comparison of Selected Tropical Fruit Crops.

Common Name

Species Name

Propagation

Growth Habit

Edible Parts, Uses

Principal Nutrients

Adaptation

 

Negative Factors

 

 

 

Temp.

Flood

Dry

Atemoya

Annona hybrid

grafts

small tree

fruit, raw

vit. C

warm

no

some

 

Avocado

Persia americana

seed, grafts

med. tree

fruit, raw

oil

warm to hot

no

some

 

Banana

Musa spp.

offshoots

large herb

fruit, raw, cooked

starch

hot

some

little

 

Black sapote

Diospyros digyna

seed, graft

med. tree

fruit, cooked

carbohydrate

hot

some

no

 

Breadfruit

Artocarpus altilis

root cuttings

med. tree

fruit, cooked

starch

hot

some

some

 

Canistel

Pouteria campechiana

seed, grafts

small tree

fruit, raw, processed

starch, vit. A & C

hot

no

some

 

Carambola

Averrhoa carambola

seed, grafts

small tree

fruit, raw

vit. C

hot

some

no

 

Cherimoya

Annon cherimola

seed, grafts

med. tree

fruit, raw

vit. C

hot

no

no

 

Citrus

Citrus spp.

grafts

med. tree

fruit, raw

vit. A & C

warm to hot

no

some

 

Coconut

Cocos nucifera

seed

tall palm

fruit, many uses

protein, oil

hot

some

some

 

Date

Phoenix dactylifera

seed,

offshoots

tall palm

fruit, dried

carbohydrate

very hot

no

yes

 

Durian

Durio zibethinus

seed, grafts

large tree

fruit, raw

protein, carbohydrate

hot

some

no

odor of fruit

Guava

Psidium guajava

seed, airlayers

small tree

fruit, raw, cooked

vit. C

hot

some

some

 

Jaboticaba

Myrciaria

cauliflora

seed, grafts

small tree

fruit, raw

vit. C

warm

some

no

needs cool winter

Jackfruit

Artocarpus heterophyllus

seed, grafts

med. tree

fruit, raw

vit. A & C

hot

some

no

 

Lansium (Langsat)

Lansium domesticum

seed

med. tree

fruit, raw

 

hot

some

no

 

Lychee

Litchi chinensis

seed, airlayers

med. tree

fruit, raw

vit. C

warm

no

no

needs cool winter

Loquat

Eriobotrya japonica

seed, grafts

med. tree

fruit, raw, cooked

vit. A & C

warm to hot

no

no

 

Mango

Mangifera indica

grafts

tall tree

fruit, raw, cooked

vit. A & C

hot

some

some

 

Mamey sapote

Pouteria sapote

seed, grafts

med. tree

fruit, raw

vit. C

warm to hot

no

some

 

Mammy apple

Mammea americana

seed, grafts

large tree

fruit, raw, cooked

vit. A & C

hot

some

some

somewhat poisonous

Papaya

Carica papaya

seed

large tree

fruit, raw

vit. A & C

hot

some

some

fruit too soft

Passion fruit

Passiflora

edulis

seed, cuttings

vine

fruit, raw juice

vit. A & C

warm to hot

some

some

 

Rambutan

Nephelium lappaceum

seed, grafts

med. tree

fruit, raw

vit. C

hot

some

no

 

Salak

Salacca zalacca

seed, grafts

small palm

fruit, raw

 

very hot

yes

no

 

Tamarind

Tamarindus indica

seed,

offshoots

large tree

fruit, raw juice

vit. C

hot

no

yes

 

White sapote

Casimiroa edulis

seed, grafts

med. tree

fruit, raw

vit. C

warm

no

some

 

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 18. Uses and Ratings (0-5) of Uses for Selected High Value Fruits

Common Name

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

Modify Climate

Avocado

5

1

0

1

1

2

1

2

Canistel

4

0

0

1

2

1

1

1

Citrus

5

2

0

1

2

1

1

1

Date

5

4

3

3

2

1

1

3

Durian

3

1

0

3

3

2

1

3

Guava

5

3

0

0

3

2

1

0

Mango

5

3

0

3

3

3

1

4

Papaya

5

1

0

0

0

1

1

0

Passion fruit

4

0

0

0

0

1

2

1

Peach palm

4

3

0

2

1

2

1

1

Pineapple

4

2

0

0

0

0

1

0

Prickly pear

3

1

0

0

0

0

1

0

Outstanding Nuts:

TN20 Figure 10

Figure 10. Guinea Peanut (Pachira glabra) fruit, similar to Malabar Chestnut (P. aquatica). Fruits split open when ripe, revealing seeds used as nuts.   Source: Tim Motis

Nuts are concentrated packages of high nutritional value, almost always protein, oil, and B and E vitamins. Most can be stored. All are good foods, and some are of gourmet quality. They are often not widely adapted but always worth producing on the small farm. In selecting nut crops for the small farm, special attention should be given to size of the tree and years to maturity. Most of the nut species (except macadamia) are not found as named varieties. Generally, special technologies for producing these species have yet to be developed. However, this does not make them less valuable.

 

 

 

 

 

 

 

 

 

 

 

Table 19. A Comparison of Nut Crops.

Common Name

Species Name

Propagation

Edible Parts,and Uses

Principal Nutrients

Adaptation

 

 

 

Flood

Dry

African breadfruit

Treculia africana

seed

seed

protein

yes

no

African walnut

Coula edulis

seed

seed

protein

yes

some

Basul

Erythrina edulis

seed

seed, foliage

 

 

 

Betelnut

Areca catechu

seed,offshoots

none

alkaloids

yes

no

Breadnut

Artocarpus altilis

seed,offshoots

seed

carbohydrate

yes

no

Canary nut

Canarium indicum

seed

seed

protein

no

yes

Cashew

Anacardium occidentale

seed, grafts

 

protein

no

yes

Coconut

Cocos nucifera

seed

seed, other

protein

yes

no

Guiana-chestnut

Pachira aquatica

seed

seed

oil

yes

no

Jackfruit

Artocarpus heterophyllus

seed, grafts

seed, pulp

carbohydrate

yes

no

Macadamia

Macadamia spp.

seed, grafts

seed

protein

some

some

Mamey sapote

Pouteria sapota

seed, grafts

pulp, seed

protein

no

some

Mexican breadnut

Brosimum alicastrum

seed

 

 

yes

no

Okari nut

Terminalia kaernbachii

seed

seed

protein, oil

yes

no

Paradise nut

Lecythis zabucaja

seed

seed

protein

some

no

Paterno

Inga jinicuil

seed

seed

carbohydrate

no

some

Peach palm

Bacrtis gasipaes

seed,offshoots

seed, pulp

carbohydrate

yes

no

Pili nut

Canarium ovatum

seed, grafts

seed, pulp

protein

yes

no

Spanish joint fir

Gnetum genemon

seed

seed

protein

some

no

Tahiti chestnut

Inocarpus fagifer

seed

seed

 

some

 

Tropical almond

Terminalia catappa

seed

seed

protein, oil

yes

no

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 20. Uses and Ratings (0-5) of Uses for Some Selected Nuts.

 

Common Name

 

Food

 

Feed

 

Fiber

 

Construction

 

Fuel

Soil Amend.

Erosion Control

Modify Climate

Breadnut

4

2

0

2

2

2

1

3

Cashew

4

0

0

0

0

2

3

1

Coconut

5

4

3

4

2

2

4

4

Indian almond

3

1

0

3

3

2

1

3

Jackfruit

4

2

0

3

3

0

0

3

Joint fir

4

2

1

2

2

2

1

2

Macadamia

5

0

0

1

1

2

1

1

Malabar chestnut

5

2

0

2

1

2

1

2

Paradise nut

3

0

0

1

1

1

1

1

Pili nut

5

3

0

2

2

2

1

2

Tahiti chestnut

3

2

0

2

2

3

1

2

Plants for Food: Beverages, Oil, Spices, and Sugar

TN20 Figure 11

Figure 11.  Nuts of African Oil Palm (Elaeis guineensis). Source: Tim Motis

The beverage crops, by themselves, are highly appreciated as stimulants but have little nutritional value. There are many good species of oil palms, particularly in South America, but the African Oil Palm continues to dominate the world’s markets. The oil from palms contains more than desirable amounts of the saturated fatty acids and is not as desirable in the diet as that of other oil sources including corn, soybean, and olives.

Spices are delightful to grow but are priced low in world markets and have little food value. Condiment herbs are useful on any small farm. Each has its special needs and its particular adaptations.

Sugarcane continues to be a common and easily grown source of sugar. Starch can be extracted from root and tuber crops, but is especially abundant in sago palms.

The production and marketing of specialty food crops is usually associated with definite regions and established markets. Some of these crops, however, may be suitable for small-scale use on the small farm.

 

Table 21. A Comparison of Some Specialty Crops.

Common Name

Species Name

Annual/ Perennial

Growth Habit

Temp.

Adaptation

 

Other uses

 

Day-length

Flood

Dry

 

BEVERAGES

Cacao

Theobroma cacao

perennial

small tree

hot

neutral

no

no

household

Coffee

Coffea arabica C. robusta

perennial

small tree

hot

neutral

no

no

household

Tea

Camellia sinensis

perennial

shrub

warm

neutral

no

no

household

OIL

 

 

 

 

 

 

 

 

Coconut

Cocos nucifera

perennial

tall palm

hot

neutral

some

some

multiple

Oil palm

Elaeis guineensis

perennial

palm

hot

neutral

some

some

 

Olive

Olea europaea

perennial

tree

warm to hot

neutral

no

yes

many

Peanut

Arachis hypogaea

annual

herb

hot

long day

no

some

as food

Sesame

Sesamum indicum

annual

herb

warm

short day

no

some

as food

Soybean

Glycine max

annual

herb

hot

short day

no

some

as food

Tung

Vernicia spp.

perennial

tree

hot

neutral

no

some

 

SPICES

 

 

 

 

 

 

 

 

Cloves

Syzygium aromaticum

perennial

small tree

hot

neutral

some

no

 

Nutmeg & Mace

Myristica fragrans

perennial

tree

hot

neutral

some

no

 

Pepper

Piper nigrum

perennial

vine

hot

neutral

some

no

 

Vanilla

Vanilla fragrans

perennial

vine

hot

neutral

some

no

 

SUGAR

 

 

 

 

 

 

 

 

Sugar cane

Saccharum

officinarum

perennial

grass

hot

neutral

yes

some

food

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 22. Uses and Ratings (0-5) of Uses for Some Specialty Food Crops.

Common Name

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

BEVERAGES

 

 

 

 

 

 

 

Cacao

1

0

0

0

1

1

1

Coffee

1

2

0

1

2

1

2

Guarana

0

0

0

0

1

1

1

Mate

0

0

0

0

1

1

1

Tea

0

0

0

0

1

1

2

OIL

 

 

 

 

 

 

 

African oil palm

2

0

0

2

1

1

3

American oil palm

2

0

0

2

1

1

1

Coconut

5

3

3

4

1

1

1

Peanut

5

4

0

0

1

2

1

Soybean

5

3

0

0

1

1

1

SPICES

 

 

 

 

 

 

 

Allspice

0

0

0

0

1

1

1

Black pepper

0

0

0

0

0

0

1

Clove

0

0

0

0

1

2

1

Nutmeg, mace

0

0

0

1

1

2

1

Vanilla

0

0

0

0

0

0

0

Sago

0

0

0

1

0

0

0

SUGAR

 

 

 

 

 

 

 

Sugar cane

3

3

0

2

1

1

3

Sugar palm

3

0

0

2

1

1

1

PLANTS FOR MEDICINAL PURPOSES

There are a very large group of plants that are used for all kinds of medical purposes in the tropics. Several problems exist in the use of such plants including the validity of the usages, the presence of a mixture of substances, the variation from plant to plant, and the difficulty of adjusting dosages. While recognizing the importance of such plants, they are far beyond the scope of this publication.

 

PLANTS FOR FEEDING ANIMALS

Feed Grasses:

The tropics are favored by many excellent grasses for forage and for cut feed. The grass selected will depend on many factors, including the level of management to be given. The literature on this subject is very extensive. Introduction of an improved grass variety and good pasture management can greatly improve animal production.

 

Table 23. A Comparison of Some of the Species of Grass Used for Animal Feed.

Common Name

Species Name

Annual or Perennial

Propagation

Growth Habit

Adaptation

Temp.

Flood

Dry

Bermuda

Cynodon dactylon

perennial

cuttings

spread grass

hot

no

some

Guinea

Panicum maximum

perennial

seed, cuttings

clump grass

hot

some

some

Kikuyu

Pennisetum clandestinum

perennial

cuttings

spread grass

cool to warm

no

some

Napier

Pennisetum purpureum

perennial

seed, cuttings

tall grass

hot

yes

no

Pangola

Digitaria eriantha

perennial

cuttings

spread grass

hot

some

some

Star

Cynodon nlemfuensis

perennial

cuttings

spread grass

hot

no

some

Sudan

Sorghum bicolor subsp. drummondii

annual

seed

tall grass

hot

no

some

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 24. Uses and Ratings (0-5) of Uses for Selected Grass Species.

Common Name

Species Name

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

Bermuda

Cynodon dactylon

0

5

0

0

0

0

4

Guinea

Megathyrsus maximus

0

4

0

1

0

0

2

Kikuyu

Pennisetum clandestinum

0

5

0

0

0

0

4

Napier

Pennisetum purpureum

0

5

0

2

1

0

4

Pangola

Digitaria eriantha

0

5

0

0

0

0

4

Star

Cynodon nlemfuensis

0

5

0

0

0

0

4

Sudan

Sorghum bicolor subsp. drummondii

0

5

0

2

1

0

1

 

Feed Legumes:

TN20 Figure 12

Figure 12.  Napier grass (Pennisetum purpureum), useful for forage.  Source: Tim Motis

Legumes are especially valuable for feeding animals because of their high nutritional value. They are seldom used alone but in mixtures with grasses. Such mixed pastures are often used in the temperate zone to increase the nutritional value of grass diets for animals. In the tropics, however, it is especially difficult to establish stable mixtures. Indeed, it has often been said that the tropics lack a good clover or equivalent. There are some special exceptions to this rule, and perhaps the best of these are leguminous, nitrogen fixing trees, often of but not confined to desert regions. Some of these trees are weedy and their introduction can have widespread ecological effects.

 

 

 

 

 

 

 

 

 

 

 

Table 25. A Comparison of Tropical Feed Legumes.

Common Name

Species Name

Annual/ Perennial

Propagation

Growth Habit

Adaptation

Temp.

Flood

Dry

Apple ring acacia

Faidherbia albida

perennial

seed

tree

hot

no

some

Centro

Centrosema pubescens

perennial

seed

vine

hot

no

some

Jack bean

Canavalia ensiformis

annual

seed

bush

hot

no

some

Leucaena

Leucaena spp.

perennial

seed

tree

hot

no

yes

Mesquite

Prosopis spp.

perennial

seed

tree

hot

no

yes

Mother-of-cacao

Gliricidia sepium

perennial

seed, cuttings

tree

hot

some

some

Prickly sesban

Sesbania bispinosa

perennial

seed

shrub

hot

no

some

Spanish tick-clover

Desmodium uncinatum

perennial

seed

vine

hot

no

some

Tropical kudzu

Pueraria phaseoloides

perennial

seed

vine

hot

some

some

Umbrella thorn

Acacia tortilis

perennial

seed

tree

hot

no

yes

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 26. Uses and Ratings (0-5) of Uses for Selected Legumes.

Common Name

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

Apple ring acacia

0

5

0

3

3

4

3

Centro

0

4

0

0

0

4

4

Jack bean

1

3

0

0

0

2

2

Leucaena

4

4

0

2

4

4

3

Tropical kudzu

0

4

0

0

0

3

4

Mesquite

2

5

0

3

4

3

4

Mother-of-cacao

2

3

0

3

3

3

3

Prickly sesban

2

3

0

3

3

3

3

Spanish tick- clover

0

4

0

0

0

4

4

St. John’s bread

4

5

0

2

4

2

2

Umbrella thorn

0

4

0

4

4

4

4

Other Feed Plants:

TN20 Figure 13

Figure 13.  Apple Ring Acacia (Faidherbia albida), often intercropped with grain crops.  Source: Tim Motis

The number of other feed plant species in the tropics is very high but few if any of these can compare to grasses or legumes in forage value.

 

Plants for Supplemental Human Needs

Fibers:

Few tropical small farms will produce their own fiber, but many will produce fiber as a crop to sell. There are many good fiber crops available. Some weeds are used as fibers.

 

 

 

 

 

 

 

 

 

 

 

 

Table 27. A Comparison of Fiber Crops.

Common Name

Species Name

Annual or Perennial

Growth Habit

 

Adaptation

 

Other Uses

Temp.

Day- Length

Flood

Drought

Cotton

Gossypium spp.

annual

large herb

hot

neutral

no

no

stuffing

Hemp

Cannabis sativa

annual

large herb

warm-hot

neutral

yes

no

yes

Jute

Corchorus capsularis

annual

herb

hot

neutral

no

no

cord

Kapok

Ceiba pendandra

perennial

tree

hot

neutral

no

no

stuffing

Kenaf

Hibiscus spp.

annual

herb

hot

longday

no

no

cord, leaves

Mahoe

Hibiscus tiliaceus

perennial

tree

hot

neutral

yes

yes

no

Abaca

Musa textilis

perennial

large herb

hot

neutral

some

no

cord

Ramie

Boehmeria nivea

annual

herb

hot

longday

no

no

cord

Sisal

Agava sisalana

perennial

herb

hot

neutral

no

yes

cord

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 28. Uses and Ratings (0-5) of the Uses of Selected Fiber Crops.

Common Name

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

Cotton

3

3

5

0

2

0

1

Hemp

1

0

1

0

0

0

1

Jute

2

1

3

1

0

0

0

Kapok

2

1

2

1

2

0

0

Kenaf

1

1

2

0

0

0

1

Mahoe

2

1

2

1

2

0

0

Manila hemp

0

0

2

0

0

0

1

Ramie

1

1

3

0

1

0

1

Sisal

1

0

2

0

0

0

1

Materials for Thatching and Weaving:

Tn20 Figure 14

Figure 14. Jute (Corchorus spp.), used to produce fiber for making twine, cloth, and burlap. Source: Tim Motis

The list of materials used for weaving and thatching would be very long. It would also vary from place to place; for any given area, many locally occurring plants are used for this purpose. Grasses are often abundant, and reeds of various kinds are also often available. Palm leaves in the entirety of their leaflets are very common weaving and thatching materials.

 

Other Materials for Making Clothes:

Cloth has often been made in the tropics by beating other fibers of a selected plant, usually the cortex,

until the fibers become a thin sheet of what could be called vegetable felt. Some of the plants are as follows:

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 29. A Comparison of Other Materials for Making Clothes.

Common Name

Species Name

Growth Habit

Propagation

Adaptation

Baobab

Adansonia digitata

large tree

seeds

dry savannahs

Mahoe

Talipariti tiliaceum

medium tree

seeds, cuttings

wet tropics

Paper mulberry

Broussonetia papyrifera

large shrub

seeds, cuttings

wide climatic adaptation

Timber and Useful Woods:

 

TN20 Figure 15

Figure 15.  Mahogany (Swietenia spp.) bark and leaves. A valuable timber species now  regulated by international trade laws.  Source: Tim Motis

The tropics have some excellent timber trees that need years for production and thus are not very feasible for the small farm.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 30. Uses and Ratings (0-5) of Uses for Tropical Lumber-Producing Species..

Common Name

Species Name

Food

Feed

Fiber

Construction

Fuel

Soil Amend.

Erosion Control

African-teak

Pericopsis elata

0

0

0

5

5

4

2

Bamboo

Bambusa spp, others

2

2

0

4

3

0

4

Intsia

Intsia spp.

0

0

0

5

5

4

2

Mahogany

Swietenia mahagoni

0

0

0

5

4

0

2

Monkey pod

Samanea saman

1

3

0

4

4

2

1

Narra

Pterocarpus indicus

0

0

0

4

4

4

2

Rosewood

Dalbergia spp.

0

0

0

3

4

3

2

Teak

Tectona grandis

0

0

0

5

4

0

2

Tropical pines Pinus spp. 0 0 0 5 5 1 2

Fuel Woods:

TN20 Figure 16

Figure 16.  Wood harvested from small woodlot (mostly Leucaena leucocephala) at ECHO. Source: Tim Motis

Many trees, if not all, can be used as sources of fuel. In this table, only the species for the hot, humid tropics are emphasized. In most parts of the tropics, wood is not used as a source of heat for the house itself. Rather, it is used only for cooking and baking. Small caliber, soft wood burns rapidly; however, dense wood burns hotter and longer for cooking. There is a great need to include fuel wood as a component of almost every small farm. When possible, farm fuel wood can be produced from the prunings of living fences and alley cropping trees.

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 31. Uses and Use Ratings (0-5) of Common Fuel Woods of the Hot Humid Tropics.

Common Name

Species Name

Food

Feed

Construction

Fuel

Soil Amend.

Erosion Control

Other

Agati

Sesbania grandiflora

2

4

1

4

4

4

pulp

Batai

Falcataria moluccana

0

0

3

4

5

5

pulp

Bracatinga

Mimosa scabrella

1

1

1

4

4

4

pulp

Calliandra

Calliandra calothyrsus

0

5

2

5

5

5

honey

Capulin

Muntingia calabura

1

0

0

3

3

1

 

Casuarina

Casuarina equisitefolia

0

0

4

5

1

4

pulp

Derris

Derris indica

0

3

3

5

5

1

insect

Earleaf acacia

Acacia auriculiformis

0

0

1

4

4

1

pulp

Gmelina

Gmelina arborea

0

0

3

4

1

2

honey

Guacima

Guazuma ulmifolia

3

3

3

4

1

2

 

Guava

Psidium guajava

5

4

3

5

1

1

 

Gumbo limbo

Bursera simaruba

0

0

2

4

1

1

fence

Honduras pine

Pinus caribaea

0

0

5

4

1

3

 

Leucaena

Leucaena leucocephala

3

5

2

3

5

4

 

Mahoe

Talipariti tiliaceum

2

0

3

3

1

3

 

Mindanao gum

Eucalyptus deglupta

0

0

4

4

1

1

beauty

Mother cacao

Gliricidia sepium

2

4

3

4

5

4

fence

Musizi

Maesopsis eminii

1

2

3

4

1

1

 

Prickly sesban

Sesbania bispinosa

0

2

4

1

4

4

gum

Red gum

Eucalyptus camauldulensis

0

0

4

4

1

1

 

Red mahogany

Eucalyptus pellita

0

0

5

4

1

1

 

Seagrape

Cocoloba uvifera

2

0

3

5

1

3

beauty

Timor white gum

Eucalyptus urophylla

0

0

3

4

1

1

 

PLANTS FOR THE FARM ITSELF: CROPS TO CONSERVE OR IMPROVE THE SOIL

Nitrogen Fixing Trees:

TN20 Figure 17

Figure 17.  Leucaena (Leucaena leucocephala), a fast-growing and multi-purpose leguminous tree.  Source: Tim Motis

Any plant that can add nitrogen to the soil in a chemically fixed, plant available form is especially valuable on the small farm. While plants of many families can do this, the ability is especially well developed among the legumes. The tropics are rich in nitrogen-fixing trees, and many of these are useful for multiple purposes such as animal feed, construction and fuel woods, alley cropping, and even minor food uses. Warning! Many of these trees are “weedy” (i.e. can become nuisance) and can cause serious ecological problems,  not only by replacing other vegetation but by mining ground water and thus lowering water tables. Therefore, widespread introduction is not recommended unless precautions are taken to avoid the development of new problems. Practices such as pruning hedgerows (e.g. Leucaena spp.) can limit seeding. Some of the best of these trees are mentioned below.

 

 

Table 32. Comparison of Nitrogen-Fixing Trees.

Common Names

Species Name

Some Uses

Adaptation

Apple-ring acacia

Acacia albida

multipurpose, animal feed

hot, dry tropics

Calliandra

Calliandra calothyrsis

multipurpose, fuelwood

wet tropics

Casuarina

Casuarina spp.

lumber, windbreak

intermediate tropics

Coral beans

Erythrina spp.

multipurpose, crop shade

wet tropics

Egyptian acacia

Acacia nilotica

multipurpose, alley cropping

hot, dry tropics

Leucaena

Leucaena leucocephala

multipurpose, alley cropping

intermediate tropics

Mother-of-cacao

Gliricidia sepium

multipurpose, live fence

intermediate tropics

Sesban

Sesbania grandflora

multipurpose, feed, food

intermediate tropics

Siamese acacia

Senna siamea

multipurpose, fuel, hardwood

intermediate tropics

Tagasaste

Chamaecytisus prolifer var. palmensis

multipurpose, alley cropping

tropical upland

Miners of Deeply Placed Minerals:

It is generally supposed, usually without rigorous proof, that deeply rooting trees, and this often includes very large trees and trees adapted to the hot, dry tropics, can obtain minerals available at deep levels of the soil that cannot be reached by shallow-rooted plants. As leaves fall from the deeply rooted trees, these minerals are then released to the soil and can be used by the shallower rooting plants. It is not possible at this time to produce a good list of such plants, but they are believed to be common.

 

Manure Crops:

TN20 Figure 18

Figure 18.  Pods (not edible) of Velvet Bean (Mucuna pruriens), a green manure commonly intercropped with corn.

Manure crops are those that are planted specifically to produce a large amount of green or dry material    that may be mixed into the soil to improve its fertility and texture. Such crops are often equally useful in suppressing weeds, or they may be used as temporary ground covers. They are planted from seeds. All of the plants mentioned in this chart can be used as feed for animals. However, feeding them to livestock limits their effectiveness as green manures and cover crops. The distinction between green manures and cover crops is minimal, and often the two words are used interchangeably. The following definitions show the difference in emphasis of the two terms. Green manure crops are those grown for the purpose of incorporation into the soil when the plant is fresh and green (thus high in nitrogen), resulting in soil enrichment and a greater water holding capacity. Ground cover crops grow vigorously to outcompete weeds and provide a good soil covering and mulch. These crops are also good for soil improvement and erosion prevention.

 

 

 

 

 

 

 

Table 33. A Comparison of Manure Crops for the Small Farm.

Common Name

Species Name

Growth Habit

Adaptation

Calopo

Calopogonium mucunoides

trailing vine

hot, humid tropics

Cowpea

Vigna unguiculata

bush or vine

intermediate tropics

Indigo

Indigofera spp.

herbs

hot, wet tropics

Jackbean

Canavalia ensiformis

bushy herb

hot, wet tropics

Sunnhemp

Crotalaria juncea

tall herb

intermediate tropics

Velvet bean

Mucuna spp.

trailing vine

tropics

Borders Against Erosion:

These important crops, chiefly grasses, are capable of growing under adverse conditions. By virtue of their deep roots and extensive vegetative growth, they serve as barriers to erosion, filtering soil being carried away from the running water, and often resulting in the filling in of deep erosion channels with collected soil.

 

0=none of the characteristic; 5=the maximum expression of the characteristic

Table 34. Uses and Ratings (0-5) of Uses of Some Borders Against Erosion.

Common Name

Species Name

Alley Crop

Nitrogen Fixing

Ground Cover

Erosion Control

Mulch

Wind Break

Shade

Lemon grass

Cymbopogon citratus

2

0

1

4

2

0

0

Napier grass

Pennesitum purpureum

1

0

0

5

2

0

0

Vetiver

Chrysopogon zizaniodes

1

0

3

3

3

0

0

Mulch:

Mulch is especially useful around crop plants to protect against loss of moisture, to reduce the temperature at the ground level, and to slowly release nutrients to the soil. No comprehensive list of such plants can be developed, for mulch is usually obtained from whatever plants are available, including the residues of crops. Casuarina is a very good source of mulch.

 

Cover Crops:

TN20 Figure 19

Figure 19. Lablab Bean (Lablab purpureus) vines covering the ground.  Source: Tim Motis

Ground covers must be distinguished from green manure crops on the basis of purpose. Some of the same species are used for both purposes. Ground covers protect the soil from erosion and intense sunlight. They also shade out weeds and can improve the aesthetic value of the land. They may be established from seed or cuttings as short- or long-term plantings. Some species of weeds (e.g. shade-loving) may flourish under long-term ground covers. Nevertheless, ground covers can be extremely useful, work-reducing plants.

 

 

 

 

 

 

 

 

0=none of the characteristic; 5=the maximum expression of the characteristic *Key to adaptation: D = dry tropics, I = intermediate tropics, W = wet tropics

Table 35. Adaptation and Ratings (0-5) of Uses of Some of the Principal Species Used for Cover Crops.

Common Name

Species Name

Adaptation

Propagation

Nitrogen Fixation

Ground Cover

Erosion Control

Mulch

Desmodium

Desmodium spp.

W

seeds

4

3-5

3-5

3

Indigo

Indigofera spp.

I,W

seeds

4

5

5

3

Jack bean

Canavalia ensiformis

I,W

seeds

4

4

3

3

Kudzu

Pueraria phaseoloides

W

seeds

4

5

5

2

Lablab bean

Lablab purpureus

I,W

seeds

4

1-5

1-5

2

Perennial peanut

Arachis spp.

I

seeds, cuttings

4

4-5

5

2

Perennial soybean

Neonotonia wightii

I,W

seeds

4

5

5

3

Sarawak-bean

Vigna hosei

I,W

cuttings

4

5

4

5

Velvet bean

Mucuna pruriens

I,W

seeds

4

5

5

3

Plants for the Farm Itself: Crops to Modify the Climate

Windbreaks:

A good windbreak should be tall but not spreading. It should be comprised of trees with roots that penetrate the soil vertically and that do not extend far horizontally. Furthermore, such trees should not spread as weeds or become difficult to control and manage. There are few such trees.

 

Table 36. Comparison of Windbreak Plants.

Common Name

Species Name

Tree Form

Other Uses

Disadvantages

Casuarina

Casuarina spp.

tall, narrow

excellent wood mulch

some species spread by root shoots

Indian coral tree

Erythrina variegata

tall, very narrow

mulch, feed, alley cropping

 

Swamp mahogany

Eucalyptus robusta

large, spreading

lumber, wood pulp

bulky nature

Tamarisk

Tamarix spp.

large, spreading

mulch, erosion control

bulky nature

Plants for Shade:

TN20 Figure 20

Figure 20.  Madre de Cacao (Gliricidia sepium), traditionally grown to shade cocoas. Source: Tim Motis

Shade is often needed on the small farm, not only for comfort around the home, but also for the same purpose over animal cages. In addition, a few crop plants, especially coffee, cacao, and vanilla are grown under shade. Shade can be obtained from trees themselves or from vines grown on trellises. A few tropical trees lose their leaves during the dry season. Others can be pruned during winter to permit more light to enter and to utilize the excess growth as fuel, wood, or mulch. The list of plants used for shade would be excessively large. Yet, with repect to trees that provide shade to other crops, a few names of prominent genera can be mentioned: Inga, Erythrina, Gliricidia, and Sesbania.

 

Plants for the Farm Itself: Other Special Purpose Plants

Living Fences:

TN20 Figure 21

Figure 21. Cuttings of Gliricidia sepium planted to form a living fence.  Source: Tim Motis

Living fences can be of great value in the tropics where termites abound and rapidly devour fence posts or iron posts rust rapidly. The ideal fence post is one that can be planted as a large cutting that can be strung with wire or animal fencing immediately, and quickly roots, and which can then be used for other purposes as well. However, a few fences are constructed as plants side-by-side without the use of wire. Hundreds of creative variations can be used.

 

 

 

 

 

 

 

0=none of the characteristic; 5=the maximum expression of the characteristic *Key to adaptation: D = Dry tropics, I = intermediate, W = wet tropics

Table 37. Adaptation and Ratings (0-5) for Multiple Uses of Some of the Better Living Fences of the Tropics.

Common Name

Species Name

Adaptation

Alley Crop

Nitrogen Fixation

Erosion Control

Mulch

Windbreak

Shade

Babul acacia

Acacia nylotica

D

3

4

3

1

1

1

Basul

Erythrina edulis

I,W

1

4

2

2

2

2

Gumbolimbo

Bursera simaruba

D,I

1

0

1

1

1

1

Hedge cactus

Cereus hildmannianus

D

0

0

0

0

2

0

Horseradish tree

Moringa oleifera

I

4

0

1

2

0

1

Izote

Yucca guatemalensis

I,W

1

0

2

0

0

0

Mahoe

Talipariti tiliaceum

W

1

0

3

2

3

3

Mother cacao

Gliricidia sepium

I

3

4

3

3

0

2

Palmillo

Dracaena fragrans

W

1

0

1

0

1

0

Pencil tree

Euphorbia tirucalli

D

0

0

2

1

0

0

Pito

Erythrina berteroana

W

4

5

3

2

1

1

Tree tobacco

Acnistus arborescens

I

1

0

1

1

1

0

Tuna (prickly pear)

Opuntia spp.

D

0

0

2

0

0

0

Plants for Alley Cropping:

As a system for crop production in the tropics, especially on hillsides, alley cropping appears promising. Some excellent plants are available, and there can be no doubt of the importance of this area of development. Unless a particular species for making the alley has been selected already in a particular region, local trial and error is always desirable. Some of the species used for alley cropping have proved to be weedy. Care must be exercised to avoid such longterm ecological damage. Frequently, hedge-row species are chosen that produce some valuable product. Alley cropping is less effective in semi-arid regions due to competition with crop plants for moisture.

 

0=none of the characteristic; 5=the maximum expression of the characteristic *Key to adaptation: W = hot wet tropics, U = upland tropics, D = dry tropics, I = intermediate, neither too wet nor too dry.

Table 38. Adaptation and Ratings (0-5) of Uses of Some of the Principal Species Used for Alley Cropping.

Common Name

Species Name

Adaptation*

Alley Crop

Nitrogen Fixing

Erosion Control

Mulch

Wind- Break

Shade

Agati

Sesbania grandiflora

I

5

3

4

2

1

1

Egyptian acacia

Acacia nilotica

D

5

5

2

2

4

4

Flemingia

Flemingia macrophylla

W

5

5

2

1

2

0

Horseradish tree

Moringa oleifera

I

4

0

1

2

0

1

Indian coral tree

Erythrina variegata

I,W

4

4

1

2

2

2

Leucaena

Leucaena leucocephala

I

5

5

2

3

1

1

Madre de cacao

Gliricidia sepium

I

4

4

2

3

1

3

Pito

Erythrina berteroana

I,W

4

5

3

2

1

1

Prairie acacia

Acacia angustissima

I,W

4

5

2

4

1

0

Pigeon pea

Cajanus cajan

I

5

4

3

3

0

0

Tagasaste

Chamaecytisus prolifer

U

5

4

2

3

0

0

 

Cite this article as:

Martin, F.W., and ECHO Staff 2007. Selecting the Best Plants for the Tropical Subsistence Farm. ECHO Technical Note no. 20.