Bio-Intensive Household Food Production - Chapter 2 - Starting a Bio-Intensive Garden

Layout for a small-scale, household level vegetable production plot

Layout for a small-scale, household level vegetable production plot

TOTAL AREA: 400-500 sq ft (35 - 45 sq m)
OUTPUT: 3-6 Ibs (1 - 2.5 kg) per day for 300 days

Important Considerations

1. Orient the rows in an east-west direction to avoid shading of the crops by the trellis.

2. Beds should not be more than 1.5 m wide to permit working on either side-of the bed without trampling on it (thus avoiding compaction).

3. Each bed should be intensively planted. It should preferably contain at least one of each of the following categories: leaf, root, legume and fruit-bearing vegetables.

4. Aromatic herbs should be intercropped in between vegetables to repel insects.

Technological profile

Plot Size: Only 20-30 sq m of "growing bed" area

Bed Preparation:

a Raised, narrow (not more than 1.5 m), deep-dug (30 - 60 cm) beds

b. Use of compost or other organic alternatives such as mudpress (0.25 - 0.75 cu m/9 sq m)

c. High labor usage initially (2-6 hours/9 sq m)

d. In humid tropics: possibility of eliminating subsequent digging of beds

e. The use of narrow beds restricts compaction to the pathways only.

f. Continuous crop cover and mulch reduces compaction (within beds) from rainfall.

Bed Fertilization:

a 0.25 cu m of compost or mudpress (by-product of sugar mills), egg shells, bone-meal, wood or cane-trash ash, ipil-ipil leaves/fish meal

b. Use of liquid manures or manure teas (fermented water-manure mixtures)

c. Inclusion of nitrogen-fixing crops into the annual crop cycle.

Crop Planning:

a Crop rotation (root, leaf, legume and fruit crops) aimed at regenerating soils and breaking pest life cycles

b. Intensive planting to achieve maximum use of space and higher yields per unit area

c. Conservation of genetic resource through the promotion of local varieties (backyard curators)

d. Inclusion of culturally acceptable, nutritionally important vegetables (amaranth, rice bean, winged bean, etc.)

e. Diversification of diet through cultivation of a wide range of vegetables or multipurpose plants

f. Inclusion of short-duration crops to deal with wet season and/or dry-season food deficiencies

g. Cultivation of trellis-crops along side the growing beds

h. Perennial, polycultural, multistoried fence crops ("edible fences")

i. Cultivation of shade-tolerant crops under the trellis.

Water Conservation:

a Close spacing of crops reduces evaporation from the soil.

b. Mulching lowers soil temperature and reduces evaporation.

c. Deep tillage and organic matter in the soil encourages water entry and conservation within bed (reduces runoff).

d. Overall a 30-50% reduction of water needs can be expected.

Weeding:

a. Significant reduction of weeding time (70% of weeding time is eliminated.)

b. Significant reduction of the growth of weeds due to deep tillage, mulching and close spacing of crops.

Pest Control:

a Soil improvement; good drainage; balanced soil nutritional status; presence of beneficial fungi (mycorrhiza) is the basis for pest reduction.

b. Crowing a diversity of crops reduces insects.

c. Crop rotation breaks the life cycle of pests.

d. Inclusion of acclimatized, hardy pest-tolerant indigenous varieties

e. Use of medicinal plants that also have insect-repellent properties (as intercrops)

f. Removal of diseased plants/plant parts prevents the spread of infestation.

g. Use of botanical formulations as pest control sprays

h. Encouragement of predatory species of insects.

Average Yield: 0. 75 kgs /9 sq m/day

The rationale for deep-dug and raised beds

More plants can be accommodated/unit area.

Increased entry of rainwater into plots and less runoff.

Reduced evaporation of applied water due to the dense crop canopy.

Applied -water is stored in lower profiles of the plot and thereby conserved.

Improved earthworm activity and nitrogen-fixing bacteria due to improved soilmoisture organic matter status.

The plots are spared from the effects of too much rain and flooding-out of rooting zones.

Plants have deeper and well-developed root systems, mitigating or delaying the impact of drought.

Permanent pathways between plots reduce soil compaction (from walking) in the growing area.

While the initial bed preparation time is 5 - 6 hours/9 sq m, subsequent preparation is only 1/3 to ¼ the time.

Improved garden microclimate (lower soil and air temperatures).

An improved garden ecosystem encourages garden predators, biotic life.

The rationale for deep-dug and raised beds

Why deep-dug beds are important?

Deep digging makes the soil loose and friable. This enables the plant roots to penetrate easily, so a steady stream of nutrients can flow into the stems and leaves.

Different plants have varying rooting depths, so extract nutrients and moisture from different points of the soil profile. The cultivation of different plants in the same part of the bed from season to season does not overburden the soil.

Why deep-dug beds are important?

Rooting Depth of Different Vegetables

Tapering Taproot of a Spinach Plant. Other crops such as celery, chicory, Chinese cabbage, collard, endive, kale, lettuce, mustard, parsley, sunflower and Swiss chard have about the same type of mot system.

Root System of a Transplanted Cabbage Plant. Brocolli, Brussels sprouts, cauliflower and kohlrabi took somewhat the same when they are transplanted.

Root System of a Transplanted Cabbage Plant

Short Taproot of a Pepper Plant. Roots of eggplant, okra and tomato are comparable

Short Taproot of a Pepper Plant

Thin Taproot of a Cucumber Plant. Cantaloupe, pumpkin, squash and watermelon have similar roots.

Thin Taproot of a Cucumber Plant

Fibrous Root System of an Onion. Garlic, leek and corn also have true fibrous roots.

Fibrous Root System of an Onion

Short Taproot of a Carrot. Parsnip and salsify roots are very similar, but the storage roots of beet, radish, rutabaga and turnip are shorter and rounder.

Wide-spreading Root System of a Pea Plant. Beans are similar.

Root System of a Potato Plant. Plant grown from a seed potato. Sweet potato and peanut roots look somewhat similar

Source: Wallace, D. et al. 1980. Getting the Least From Your Garden. Rodale Press, Emmaus, Pennsylvania. 

Development of rooting systems

Root distribution depends upon the

(1) depth of the plowed or dug area.

(2) depth of top soil.

(3) downward movement of applied water or rain.

(4) amount of air available.

(5) depth of placement of fertilizer or other nutrients.

Raised-bed garden technologies

1. Measure about 1 m by 6 m bed area. (The length can be altered depending on the availability of land.) Divide the bed temporarily into sections, 75 cm wide using wooden stakes as guide.

2. Spread evenly a 8-cm thick layer of compost over the bed.

3. Dig a trench 30 cm deep and 75 cm wide at one end of the bed. Place the soil from this trench on one end of the bed.

4. Dig a second trench adjacent to the first one. Cover the first trench with the soil coming from this trench.

5. The process is repeated until it reaches the other end of the bed. Fill the open trench at the other side of the bed with the soil previously dug out from the first trench. (See step 3.)

6. Apply the following into the bed: 2.5 cm compost or decomposed manure or mud press, 1 kg wood ash, 1 kg bone meal, 0.5 - 1.5 kg fish meal or dried leaves of leguminous trees and 1 kg Ibs of any of the following: crushed egg shells, snail shells, etc.

7. Mix these plant foods thoroughly into the top 15-cm layer of the soil. Level the bed. It is then ready for planting.

Note: The same natural amendments are added to all the other options of bed reparation.

Raised-bed garden technologies

For rocky and waterlogged areas, soil can be taken from other sources and formed into a bed using artificial sidings like banana trunks, coconut trunks, wood planks, etc.

For rocky and waterlogged areas

For very hard soils, initial digging of 15 cm can be made. Then beds can be raised further by getting soil from the sides of the bed.

For very hard soils

Double digging is one way of upgrading the soil structure by improving soil aeration and waterholding capacity at the lower depths of the soil. Instead of 30 cm, the soil is dug 60 cm deep.

Double digging is one way

Integrated alley cropping bio-intensive garden

Integrated alley cropping is a form of intercropping vegetable plots between rows of fast-growing trees or shrubs. It is applicable in areas where animal manure/compost is not available. Its main purpose is to provide a steady and reliable source of organic material to crops. Since these hedgerows are legumes which fix atmospheric nitrogen. they add a continuous supply of this element as well as valuable organic matter.

Integrated alley cropping bio-intensive garden

Important Considerations

1. Select fast-growing and nitrogen-fixing trees/shrubs that can withstand frequent pruning.

2. Some potential alley-cropping tree hedgerow species: Gliricidia septum Calliandra calothyrsus Flemingia macrophylla Cassia siamea

3. Orient the rows in an east-west direction to avoid shading of the crops by the hedgerows.

4. Rows of trees/shrubs should have a minimum space of 5 m to allow more space for vegetable crops.

5. Soil should be dug and loosened to a minimum depth of 30 cm.

6. Plant tree/shrub seeds and vegetables crops at the same thee.

7. Pruning is first done after the trees are 9-12 months old. Trees are cut 0.5 m above ground level.

Hedgerows Lopped and Incorporated into Beds

Procedure

1. Cut the trees when they are about three meters in height or the stem diameter is more than one centimeter. Subsequent cuttings are done whenever leaves are needed or die trees begin to shade the garden plots. Leave one branch/tree longer to ensure regrowth in the event of very dry weather.

2. Place cut branches of tree hedgerows (within leaves) over the entire bed.

3. Leave them in place for two days. This will allow the leaves to wilt and hasten defoliation.

4. Shake branches or use hand to remove remaining leaves. There should at least be a 8-cm layer of leaves over the entire bed. (The branches can be used as fuel for cooking.)

5. Incorporate leaves into the soil to a depth of 15 cm.

6. Allow leaves to decompose for 10-14 days. If possible redig the bed once or twice to turn over the incorporated materials.

7. After another 10-14 days apply necessary soil supplements like 1 kg of wood ash 1 kg of eggshells and 1 kg of crushed bones (where these are available). (Rates mentioned are for a 9 sq m bed area.)

8. Shape the bed and plant.

Pot-garden technologies

Containerized gardening is very appropriate in areas where space is limited. It is one of the important features in urban gardening. A lot of vegetable crops can be grown with their roots contained. They can perform as well as when they are in the ground.

A general poking mixture for most plants is: 1 part garden soil, 1 pan coarse sand and 1 pan compost. Whatever container is used, it is important that it drains freely - It should have hole(s). Enough coarse gravel should be placed in the bottom of the container so that the dim will neither sift through the holes nor clog them.

Herbs and some leafy vegetables (shrubs) are best grown in pots:

Productive vine crops can be grown in hanging baskets.

Common garden tools

The ease of gardening depends largely on the use of right tool in the right way. The proper tools will also make the work more productive.

Common garden tools

Reference Source: International Institute of Rural Reconstruction