Planting

1.1. Propagation

Avocado trees are propagated by grafting or budding scions of desirable cultivars onto seedling or rootstocks. Avocados can be grown from seeds, but fruit quality and yield potential will be quite variable. Grafted or budded avocado trees usually produce fruits when three to five years old, while seedlings often require five to seven years.

1.2  Nursery care

Seeds should be harvested from selected tree (not picked from the ground) and after removal of the pulp, care should be taken, in planting them as soon as possible in the nursery in order to avoid drying out. It is common the infection of Phytophthora cinnamoni (avocado root rot) and to eliminate this fungus, seeds should be sunk in hot water at 50⁰C for 30 minutes before planting. Germination of the seed is hastened by removing the brown seed coats and cutting a thin slice from the apical and basal end of each seed before planting.

The seed coat can be removed by wetting the seeds and allowing them to dry in the sun. The seed should be placed in the soil with the large basal end down, just deep enough to cover the tips. Seedling should be ready for grafting after  5 -6 months. The propagation by seed-for rootstocks production is a necessary step before grafting with improved varieties (taken from well identified mother plants). The planting distances depend on altitude, soil type/fertility, cultivar and climatic influences. Wider than normal spacing is necessary if the soil fertility is poor, maintenance inputs are limited and plants depend mainly on rainfall. Overcrowding leads to increased infestation with pests and diseases and will consequently reduce yield and income. Depending on the above-mentioned variables, recommended tree spacings are indicated in the cultivar descriptions. In Rwanda, 4-5 m x 4-5 m spacing is recommended; planting density of 400-625plants/ha.

1.3 Transplanting

Prior to planting, planting holes measuring 80m x 80m x 80 m are recommended. Top soil should be placed in one pile and subsoil in another. The hole should then be refilled with a mixture of 50 % top soil and 50 % of well rotten manure, compost, or other decomposed organic matter (50 kg/hole).

Container grown plants should be removed from their pots and any circling roots should be cut off in several places or loosen them. Soil is removed from the prepared holes and any stakes should be inserted firmly into the planting hole (to give support to the tree for the first two years); the plants are then set and covered to the same depth that they were growing in the container.