Nature of cassava
Soil
Cassava grows best on light, sandy loams, or on loamy sands
which are moist, fertile and deep, but it also does well on
soils ranging in texture from sands to clays and on soils of
relatively low fertility. In practice, it is grown on a wide
range of soils, provided the soil texture is friable enough
to allow the development of the tubers.
Cassava can produce an economic crop on soils so depleted by
repeated cultivation that they have become unsuitable for other
crops. On very rich soils the plant may produce stems and leaves
at the expense of roots. In some parts of Africa, freshly cleared
forest soils are regarded as highly suitable after they have
borne a cereal crop.
Fertilization
No fertilization is required when the land is freshly cleared
or when there is enough land to enable the cultivator to substitute
new land for old when yields fall. Like all rapidly growing
plants yielding carbohydrates, cassava has high nutrient requirements
and exhausts the soil very rapidly. When cassava is grown on
the land for a number of years in succession or rotation, the
soil’s store of certain nutrients will be reduced and must therefore
be returned to the soil by fertilization.
Various experiments in Brazil, India, Africa and the Far East
have shown significant increases in yield - of roots as well
as starch content - obtained by the application of fertilizers.Potassium
salts favor the formation of starch, and nitrogen and phosphorus
are essential for growth. However, if the soil contains large
quantities of assimilated nitrogen, the result will be heavy
development of vegetative growth without a corresponding increase
in root production.
Generally speaking, fertilization is practiced at present in
most parts of Africa and South America only on commercial plantations.
In Thailand, only a few farmers apply artificial fertilizers,
as they are usually too costly for the small farmer. Most farmers
use different kinds of organic manures, such as cattle or duck
manure or garbage.
The kinds and quantities of fertilizers required by a cassava
crop depend on the nature of the soil.
| Nature
of cassava |
 |
|
