The most common fruit trees--apple, pear and stone-fruits--lose their leaves in winter. However, it is possible to grow fruit on a tree that stays green year round, especially if you live where the summers are long and warm and the winters chill. Fruits produced by evergreen trees tend to be soft and juicy.

This evergreen has been around almost as long as human civilisation. Olive seed found in Spain were carbon-dated at 8,000 years old. True to its Mediterranean roots, the olive demands a long, hot summer to ripen its fruit and a sufficiently chilly winter to ensure fruit set. This attractive tree may get as tall as 50 feet, with a 30-foot spread. Its grey-green foliage is distinct in an all green garden. The olive fruit--a green drupe--can be green or black upon maturity.

Mango trees--erect and fast growing in the proper climate--make handsome ornamental shade trees. While the tree can grow to 65 feet, it is often half that size in California. Some mango trees have lived more than 300 years and continue fruiting. Mango fruits grow at on a long, stringy stem about 9 inches long, and range from 225 to 680 grams (8 to 24 oz). Just under the thick, waxy skin is juicy flesh, sweet and peachlike, with many fibres radiating from the husk of the single large seed.

The best known member of the soapberry family, the lychee tree is a handsome evergreen that can attain 100 feet in both height and width. Its leaves are 5 to 8 inches long. While the tiny, petal-less flowers are pale-green, the emerging fruit comes in a showy display of 2 to 30 bright-red globes hanging in a cluster. The thin, warty skin peels easily when the fruit is fresh, exposing the juicy aril; it looks somewhat like a peeled grape. The lychee is native to southern China.

Nicknamed the alligator pear for its green scaly skin, the avocado tree sheds its leaves only in dry seasons and then only for a brief period. A mature avocado tree will either stand erect between 30 and 60 feet high, or else it will grow as a low, spreading bush. Its leaves are shiny green on top, whitish on the underside, while the fruit varies from 3 to 13 inches long. Immediately under the thin, rough skin is the buttery fruit, which is yellow or green in colour. Most avocados are grown in Mexico, the Dominican Republic, California and Florida.