During the growing season keep the compost moist and feed with a balanced liquid fertiliser every month to ensure it produces a good crop of fruit.
Prune olives in early spring to keep an attractive shape and to remove any dead, diseased or dying branches. To restrict the size of a pot-grown olive, tip prune the main branches, cutting back to a good replacement shoot each year.
Many olives are hardy, but branches can still be damaged by severe frosts. Store in a frost-free place if grown in pots or cover the branches with horticultural fleece.
Plants grown in pots should be raised up on pot feet to allow excessive moisture to drain away.
Do not move pot-grown plants outside for the summer until all danger of frost has passed.
Olives are available in many sizes from mature old trees with beautiful gnarled trunks that make the perfect focal point in a large garden, to half standards that take up very little space.
Plants can be planted in the soil in cool climates if you have a very sheltered town garden, but are more suitable for growing in large containers that can be given a sunny-spot outdoors in summer, then moved into a frost-free place overwinter.
Planting in the ground is best carried out in spring. Select a well-drained, sheltered site against or near a sunny wall. Stake plants until established.
Alternatively, plant in 30-35cm (12-14in) pots (or large enough to accommodate roots comfortably) filled with gritty, loam-based compost, mixing in some controlled release fertiliser granules.
Mealybug: Small creatures covered in a white ‘meal’ cluster in inaccessible spaces like leaf joints or under loose bark. They suck sap and secrete ‘honeydew’ which causes black sooty mould on the leaves.
Remedy: Use biological controls and encourage ladybirds.
More info on Mealybug
Olives are ready for harvesting in autumn. Ripe green fruit will eventually turn black and firm on the plant. If you like green olives they will need soaking in salted water for several days to remove any bitterness and make them palatable. Black olives need dry curing in salt for several weeks until dehydrated then storing in olive oil or brine.