The vegetable garden in the tropics - Journey to Forever

tuce)need large amounts of nitrogen. Beds on which you want to
grow tomato, eggplant or carrots shouldn’t get too much N because
this would favourgrowth of the leaves, instead of the roots and fruits.
Signs of deficiencyare: small and deformed plants, particularly small,
light or yellowish green leaves and premature browning of the bottom
leaves, while the top of the plant stays green.
2 Phosphorus, (phosphate), represented by the symbol P, is necessary to
formseeds and flowers, and to increase disease resistance. It is
needed especially for seed and fruit vegetables (tomatoes, pepper,
okra, beans) and for root vegetables (carrots). Signs of deficiency are:
stunted growth, light green leaves often purple or brown at the tips
and edges, slow and often etiolated development, and few fruits and
seeds.
3 Potassium, represented by the symbol K, stimulates development of
rootvegetables (carrots, radish, cassava) and tubers (sweet potato, potato)
and is also important for onions and tomatoes. Potassium helps
the plant to resist drought and diseases. Signs of deficiency are: white
yellowish or reddish spots on the leaves, starting at the leaf edges
(especially of the lower leaves), which turn yellow, red or brown and
finally dry out and die, and stunted growth.
6.3 Organic manure
Organic manure provides the soil with humus and all the nutrient elements
necessary for plant growth. The humus makes the soil easier to
cultivate and increases its permeability and its retention capacity for
water and nutrients. Organic manures are: dung, compost, litter and
green manure. The necessary amount of green manure is at least 1kg per
kg harvested vegetables or 2.5kg anure per square metre, to be worked
in before each sowing.
Dung
Dung is obtained by fermentation of faeces and litter of animals. It
makes the soil very fertile. Some animals give better dung than others
(in decreasing order: poultry, horses, sheep and goats, cattle, pigs). To
get good dung, the bedding of the animals must be abundant and re-
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The vegetable garden in the tropics