Planning the crop
Avocados are evergreen trees native to Central America. As a result, most varieties are sensitive to cold and frost. Purchase a named variety tree from a nursery – it should begin fruiting about three years after planting. Trees raised from seed can take 7–10 years to bear fruit, which may well be poor quality. Trees need very good drainage and a deep soil. If you need to, create a large, well-raised garden bed or mound so that a total depth of at least 1 m of soil is available to the roots.

How many to grow- In subtropical to tropical areas you do not need to plant two different varieties to achieve a good fruit set. In Mediterranean-climate areas it is advisable. Allow 8 m around each tree.

Varieties- Guatemalan varieties have thick, rough-skinned fruits in spring to summer, with some cold resistance. West Indian varieties have large, thin-skinned, smooth fruits in summer. They are quite cold sensitive. Mexican varieties have smooth skinned fruits borne in summer to autumn. They have the greatest cold resistance of all varieties. Good garden varieties for growing in warm temperate to tropical areas are Rincon, Wurtz and Pinkerton, which all have restrained growth. Self-fertile Bacon performs well in cool climates. Some wonderful eating varieties, such as Fuerte, Hass and Sharwill, need very deep, rich soils, so are not suited to most gardens.

Growing tips
The best time to plant avocado trees is in spring, from September to October. Two months before planting, while preparing the ground, add compost and well-rotted manure to avoid the delicate roots being burned. Once the plant is established, apply an organic mulch and a light dressing of potash (or wood ash) annually. You can also apply well-rotted manure and compost. The soil should be limed every three years. Fruit drop tends to happen around midsummer and is quite normal – the tree is shedding excess fruit at the immature stage. But unnecessary fruit loss is caused by the soil drying out. Prune trees back by one-fifth each year after fruiting has occurred.

Pests and diseases
Problems in avocado trees often have environmental causes. Varieties that flower well but, disappointingly, never fruit are almost certainly suffering from too cool a climate, although low bee populations may also be a cause. Shepard and Sharwill varieties can be badly affected by alternating hot and cold periods in spring. Other varieties may be better suited to your district. Phytophthora root rot is the most serious disease – good drainage is essential. Buy certified disease-free trees. Anthracnose may also be a problem. Red spider mite and fruit borers are the main insect problems.

Harvesting and storing
Knowing when to harvest is quite tricky. The skin of the fruit will begin to dull. But a good indicator is when the first fruit falls to the ground. It will be fully ripe two weeks later. You can harvest the other fruits progressively, as you need them.

At-a-glance timetable
Planting September to October
Harvesting depends on variety. After the very first mature fruit drops, harvest progressively.
Pruning after fruiting