How to grow kumquats, lemons, limes and lychees

While some subtropical fruits, such as these, may survive outdoors only in Canada's warmest of growing regions, southwestern British Columbia, they can also be grown indoors in pots for anyone to enjoy.

Kumquats have tiny fruits that are bitter when eaten raw. They make the most delicious jams, jellies and fruit liqueurs. The marumi (Fortunella japonica) has pretty round fruit, while the fruit of the nagami (Fortunella margarita) are oval shaped. Kumquats can be grown in tubs on a sunny sheltered balcony, and they have the same basic requirements as citrus in terms of climate, soil conditions and feeding.

Lemon trees have overlapping crops, so it is possible in some climates to have fruit on the tree most of the year. Popular varieties include 'Lisbon', 'Eureka', 'Meyer' and 'Prior Lisbon'.Good soil conditions are necessary for healthy growth, and routine feeding with a specially formulated citrus food will produce good results — in winter, approximately 500 grams (one pound) for each year of the tree's age with a dressing of nitrogenous fertilizer in early summer. Remove suckers that emerge at the base of the trunk, and prune out dead wood from the centre as required.

Limes can be a useful citrus tree because they are much more resistant to cooler temperatures. Like the kumquat, they have a bitter flavour but are useful for making marmalade and concentrated fruit cordial. The most popular lime variety is 'Tahitian', although a seedless variety with a pale skin, called 'Persian', is also available.

Lychee trees are attractive and evergreen, growing as high as 12 metres (39 feet) when mature. They are best in a subtropical climate which has a dry autumn but plenty of rainfall over the rest of the year. The most commonly grown variety is 'Brewster', although 'Kwai Mi' and 'Mauritius' are also worthwhile varieties. The fruit is small and round with red, leathery skin and white, juicy flesh.

Growing from seed is not reliable, so it is best to buy a young grafted tree. The tree must have deep, well-drained soil and should be fed annually with plenty of organic matter to ensure good fruiting. Lychees will not bear fruit for the first four or five years but after that should fruit reliably for many years.

Ripening happens over a five-week period during the wet season. Harvesting is done by cutting off the branches holding the fruit clusters — this helps to keep the new growth to the outside of the tree.