Avocado fruits are among the more expensive fruits in Kuala Lumpur and Singapore. The fruits are imported from Australia and sold in supermarkets to expatriates and to the few locals who have acquired a taste for them. The majority of Malaysians and Singaporeans think avocadoes are awfully bland, or just plain awful.
However, in the Malaysian state of Sabah, close to the Philippines, where there is a large population of immigrants from the Philippines, avocadoes are cheap, locally grown, and sold by roadside hawkers. The quality, size and shape of the locally-grown fruits is very variable.
The avocado is native to tropical America, and was introduced to the Philippines by the Spanish in the 1600s. The Philippinos have had 400 years to learn to love the fruit, but according to Burkill's Dictionary of the Economic Products of the Malay Peninsula, it was not love at first sight.
The Indonesians got their first taste in the 1700s. They have learnt to love the fruits, and blend it with palm sugar to make a rich nutritious drink.
Avocados were introduced to Malaysia and Singapore by the British in the late 1800s. British rubber planters often had an avocado or two growing in their bungalow gardens.
In all the books on growing avocados, we are told that single trees will not fruit because they need cross-pollination by another tree. The trees in Malaysia ignore this rule. Single trees often produce good crops of fruits. However, after having experimented with avocados for over 30 years, I can say they are extremely variable in behaviour. I have seen trees begin to fruit at 5 years, trees that did not fruit until after 10 years, trees that never fruited at all in 20 years. Fruits vary in size, shape, colour, smoothness / roughness of the skin, thickness of the flesh, quality of the flesh (creamy, lumpy, etc). A lot of work will have to be done in testing and selection before we can have a good reliable clone for our particular climatic and soil conditions.
To grow an avocado it is best to use a seed from a tree that is proven locally (e.g. known to produce abundant fruit of good quality at an early age). Seeds from another country may produce healthy trees but such trees are likely to be unfruitful.