Cultivation notes

Kiwi fruits are vigorous plants that need plenty of space. They should be planted 3-4.5m (10-15ft) apart. Plants start to produce fruit three to four years after planting.

Self-fertile cultivars are ideal where there is space for only one plant. Otherwise for successful pollination both female and male (non-fruiting) plants should be planted. One male plant can pollinate up to eight females and should be sited 60cm (2ft) away from one of the females.

Site and soil

Kiwi fruits require a sheltered sunny position, preferably a south- or west-facing wall, although they can be grown in the open in milder areas. Young shoots are extremely vulnerable to frost damage in the spring and may require protection.

They grow best in a fertile, well-drained slightly acid soil which is rich in organic matter.

Aftercare

Mulch around the base of the plant with well-rotted manure in late winter, avoid contact with the stem as this may cause rotting. Apply a general-purpose fertiliser such as Growmore at a rate of 70g per sq m (1oz per sq yd) when growth starts in the spring.

Water well to keep moist during the growing season. This may need to be done as often as two or three times a week in hot dry weather.

Harvesting

Kiwi fruit should be picked before the first frosts and placed with other ripe fruit in the fruit bowl to encourage ripening. They should be ripe in a few weeks. Harvested fruit will keep for up to three months in a pierced plastic bag in the refrigerator.

Pruning and training

Kiwis are best grown as an espalier. First establish a training system against a wall or fence; our web profile about espaliers gives more details of a suitable framework.

Alternatively, kiwi fruit can be trained over a pergola, allowing laterals to develop once the top of the pergola is reached.

Initial training

• After planting, cut back to 30cm (1ft). Tie in the new leading shoot to a cane attached vertically to the wires
• Train in a pair of shoots to grow along each horizontal wire. Pinch out the tips when they fill the allotted space
• Allow lateral shoots to develop at 50cm (20in) intervals
• Pinch out the tips of these shoots after they have developed five leaves – these will produce fruit the following year

Winter pruning

• Cut existing laterals back to three or four buds beyond the last fruited stems
• Each year cut back about one-quarter to one-third of the oldest laterals to a bud around 5cm (2in) from the main stem. New growth will be produced from this stub in the growing season

Summer pruning

• Summer pruning is important to keep these vigorous plants in check
• During the growing season, pinch out any sideshoots that have developed from the laterals and any further shoots arising from the main arms. These short shoots will also produce fruit in the following season
• Once the fruit has set, pinch back the side shoots leaving four or five leaves beyond the maturing fruit
• Any non-fruiting laterals can be cut back to five leaves from June onwards

Propagation

Softwood cuttings can be taken in the spring; alternatively, named cultivars can be grafted using whip and tongue grafting. Layering may also be tried.

Cultivar Selection

Actinidia deliciosa 'Hayward': (female) The most widely grown kiwi. It is very late flowering and produces large, broadly oval fruits with good flavour.

A. deliciosa 'Tormuri': (male) This is a late-flowering cultivar suitable for pollinating Hayward.

A. deliciosa 'Jenny': (self-fertile) well-flavoured fruits.

A. arguta 'Issai' (hardy kiwi): Small fruits about the size of a grape ripen in July or August and can be eaten whole. Actinidia arguta is self-fertile and requires the same growing conditions as other kiwis.

Problems

Drought stress will cause drooping leaves, brown edges to the leaves and even complete defoliation.

Leaf scorch may show as brown edges to the leaves and may be caused by drought or drying winds.

Nutrient deficiencies may also be a problem, particularly on chalky soils.

As with many other woody climbers, kiwi fruit may succumb to honey fungus or Phytophthora root rot.