Global agricultural practices for successful cashew development
Practical Action
Two or three seeds should be planted together, stem end up, at a slight incline and covered
with 5-8 cm of soil. Germination usually takes place in 15-20 days, although seeds of low
density (i.e. those that float in water) may require as long as eight weeks to germinate. Using
seeds of high density, from selected trees, considerably increases the chance that some of
the seeds at one site will perform well. Two months after sprouting, the two weakest seedlings
should be removed from the site, leaving only the strongest one to grow. By planting more
than one seed, the occurrence of gaps in a plantation is
reduced (Ohler, 1979').
In orchard practice, pits measuring from 30 cm x 30 cm x 30 cm to 60 cm x 60 cm x 60 cm
are dug and left to weather for a month or two. They are then filled with soil which has been
mixed with rotting manure about two weeks before seeding. In loose soils of sufficient
fertility, the root system of the seedlings develops so quickly that, when growing naturally,
root lengths would exceed the size of the planting hole within a few months and therefore in
optimum growing conditions planting holes are not essential.
Advantages of sowing
• The plant can develop its root system and especially its root tap quickly.
• It is the cheapest method of planting.
• It is the quickest method of planting - one person can plant 400-500 sites each day.
Disadvantages of sowing
• Lower rate of germination.
• Danger of serious damage by animals.
• Less opportunity for selection of seedlings than when planting seedlings that are raised in
plastic bags in the
nursery.
Seasonal planting
In areas without irrigation facilities, cashew seeds should be sown or planted in the rainy
season. The best time for planting is when the rains have started to fall regularly so that the
soil does not dry out again. If the soil dries out before the germinated seeds have become
securely rooted, they may die. The advantage of early planting is that it gives the seedlings
more time to develop before the dry season starts.
In climates with irregular rainfall and short rainy seasons, the risk of germinated seedlings
drying out can be reduced by pre-soaking the seeds before planting, deep sowing (5-10 cm)
and covering the site with mulching material to reduce evaporation. The mulching material
should be carefully selected, and any weeds with mature seeds should be removed.
Raising seedlings in a nursery
Where it is necessary to raise seedlings in a nursery, the seeds should be sown in containers of
a type that can be set in the ground and readily disintegrate. In Cuba, baskets of uva-grass or
cona brava are used, and cut away before setting the plant into the ground. In Jamaica, it has
been found that nursery seedlings can be raised in the ground and transplanted with 90%
success, providing the plant is taken up with a good ball of soil and the top is cut back by one
third when it is put into the field. It is recommended that the seedlings are transplanted
within a week of emerging, to ensure that the transplantation is successful (CTCS, 19932).
Seedlings can also be planted using plastic bags as containers. The seedlings should be
lifted into their planting holes in the plastic bags, which are then carefully slit with a sharp
knife and removed.
Air-layering
Air-layering has been one of the most successful methods of vegetative propagation in cashew.
The method is rather laborious and the cost is relatively high, but the advantages of obtaining
a plantation from high yielding, uniform material make these costs extremely worthwhile. A
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