GROWTH CONDITIONS
Growth period: with seedling trees, the first fruit can appear in 5–6 years.
Vegetatively propagated trees produce fruit earlier. They tend to be biennial bearing
ie they normally only produce a good crop of fruit every other year.
Temperature: requirements vary according to the type/race see introductory
paragraph, above.
Rainfall: minimum is about 750 mm per year, ideally not evenly distributed but
with alternate wet and dry seasons.
Pruning: little is necessary, other than to remove suckers from the rootstock and
any dead wood. Upright varieties often have the central shoot pruned so as to
produce a more spreading growth habit. The branches of spreading varieties are
sometimes thinned or shortened. The tops of tall trees are sometimes removed to
make harvesting easier.
Wind: windbreaks are often necessary, as the wood is soft and breaks easily.
Pollination: most varieties are cross-pollinated, mainly by bees. Some varieties
either require or benefit from another variety growing nearby to act as a pollinator,
especially in hot regions. Other varieties are self-fertile.
Pests: some damage can be caused by scale insects, mites and mealy bugs. The
sugar-cane root weevil can also give problems, in Puerto Rico for example.
Diseases: Root Rot (Phytophthora cinnamomi) is the most serious, sometimes
killing the tree; often associated with wet soil. Other diseases damage the fruit and
leaves, such as Cercospora Spot, Anthracnose (Black Spot) and Scab.
Trace elements: deficiency of Zinc and Copper can cause symptoms (1Cd, page
23).
YIELD
Typical weights of fruit:
Mexican types: 90 g–240 g;
Guatemalan types: 240 g–2.2 kg;
West Indian types: 1–2 kg.
The average yield of avocado is 100-500 fruits per tree per annum. In North
America and elsewhere, good orchards can produce more than 13 MT/ha per annum.
UTILISATION
LIMITATIONS
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shaped fruit is 5-6 cm long and contains no seed.246 TONY WINCH
Avocados are normally eaten as a salad fruit; they are most nutritious when
eaten raw, such as in guacamole, ice cream and milk shakes.
The pulp can be preserved by freezing.
Avocado oil is used in cosmetics and toiletries.
The cocktail avocado is grown in Chile, South Africa and Israel. The bulletAvocado trees have a tendency to biennial bearing habit.
With seedling trees, 5 or 6 years may elapse before the first fruit is produced.
Seedling trees are not always satisfactory, while vegetative reproduction
techniques require specialist knowledge.
Some varieties need other varieties as pollinators.