Avocado Production in Asia and the Pacific - United Nations in ...

4.3 Planting
Planting is carried out at the beginning of the rainy season (May-June). The plants
should have no sign of insect pests and diseases on the stems and leaves and they should be
subjected to hardening under full sunlight before transferring to the field. The plants are
brought to the prepared holes and are removed from bags or containers. They are then
placed in the hole, with soil mixture filled and firmed to ensure good contact with roots.
They are then watered regularly to ensure availability of sufficient moisture until
establishment. Insecticides are sometimes applied to protect from termite damage every
three months and also fungicide, often by using 100 grams of metalexyl (Ridomil 50 g)
granules around each plant. The plants are protected from wind by planting windbreak trees
as well as by using bamboo stakes for supporting newly planted trees.
4.4 Mulching
Plastic sheets can be used as mulching material but this is not seen commonly in
Thailand. Often, organic materials such as straw, rice husk and wood chips are commonly
used as mulching material because these materials can later decay and become available to
plants as organic fertilizer.
5. CARE AND MANAGEMENT OF ORCHARDS
5.1 Training and pruning
Avocado trees are normally trained under a modified leader or open centre system.
When plant height of newly established plants is about 70 cm, the growing tips are pinched
off to allow development of more side shoots to form a round-shaped tree. After harvesting,
the trees should be pruned. The upright branches, water sprouts, dead wood, infected
branches, and the branches that are not exposed to the sun should be pruned off.
5.2 Fertilizer application
A mixed fertilizer of 46-0-0 and 15-15-15 at 250 grams/tree is applied two months
after planting and the same rate is repeated again three months later. The same formula with
a slightly higher rate of 300 grams/tree is applied in the second year at the beginning of the
rainy season with repeated applications every three months. From the third year onwards, as
well as for bearing trees, the amount of applied fertilizer depends on the radius of the tree
canopy, i.e. at every one-meter radius, one kilogram of mixed fertilizer of 46-0-0 and 15-15-
15 is applied.
5.3 Weeding
The weeds are often cut, as ploughing to control weeds is not recommended because
of the shallow root system of the trees. Some growers use contact or systemic herbicides for
chemical weed control.
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