Growing Kiwi Fruit

Kiwi Fruit originally come from China. It was introduced to New Zealand in the mid-1800's. Not much interest was taken in it until the 1930's when it was started to be grown commercially but it is only since the 1960's that it has become a major crop. In recent years a great deal of study in cultivation methods and selection of breeding has been carried out.

Most Kiwi fruit plants are unisexual, i.e. being all male or all female. Therefore 2 plants will be required for pollination of the fruit. There is only one variety that is self-pollinating; this is 'Blake', so if only 1 plant is being grown, it is recommended to grow this variety.

Other varieties include: -

Female plants - 'Abbot', 'Bruno', 'Hayward', (this is reputed to be the heaviest cropper).

Male plants - 'Matua', 'Tomuri', 'Atlas' and 'All Purpose'.

Purchasing Stock

Kiwi plants are usually grafted onto a rootstock, occasionally you may find seed or seedlings for sale but it is not worth bothering with these as they rarely come true to type. You will also have to wait a number of years to find out their sex and it is unlikely to produce any worthwhile fruit.

Soil Conditions and Siting

Kiwi Fruit will grow in any soil as long as it is moisture retentive and well drained. The soil should be slightly acidic but the plants will tolerate a mild alkalinity as long as they are fed with sequested iron. The soil should be well improved with compost or manure especially if it to be planted against a wall where the soil is usually dry and impoverished.

Kiwi will tolerate winter frosts but need their flowers protecting against frost in spring. Their branches can be a bit brittle so it is recommended that they are planted in a sheltered site.

Planting

Kiwi Fruit are usually sold as grafted, container grown trees. They can be planted at any time of the year but it is recommended that they be planted in the autumn or kept extremely well watered. If planting more than one tree, allow 20ft (6.5m) between them.

When planting against a wall, allow 8 - 10" (25cm) away from the wall.

1 male plant should be planted for every 5 female plants.

Maintenance

Feeding

In early spring feed with 1oz (34g) per sq. Yard (sq. metre) of Growmore or Fish, Blood and Bone. Follow this with a mulch of well-rotted manure o compost to help retain moisture.

Watering

Ensure that the tree is well watered in the spring and summer but reduce the watering in the final stages of the fruit swelling. This is different to most fruits but is important in helping the fruits to ripen.

Pruning

Against a Wall - After planting cut back the main stem to just above the lowest wire and tie it to the wire. As new shoots appear, tie one vertically and the two laterals to the wires. Cut out any others. Repeat this process until the desired height is reached. When the lateral shoots reach 3ft (1m) pinch out the growing tips. This encourages side shoots to form and these in turn should be pinched out five leaves from the base. By the third year these shoots should be producing fruit and will become fruit spurs. These should be pinched out five leaves beyond the fruit cluster. In the winter all the side shoots should be cut back either to two buds beyond the base if they didn't fruit or to two buds beyond the fruit cluster if they did fruit. This process is then repeated in subsequent years.

On Free Standing Wires - After planting, cut back the main stem to a height of about 24" (60cm) and insert a firm stake next to each plant. Tie the stem to the support and, as new shoots develop, select the strongest and train it up the stake, cutting out all the others. When the main stem reaches the wire, pinch it out. Again more shoots will appear, select the two strongest and train them along the centre wire. Pinch out all the other shoots. Side shots will arise from the two and these should be tied laterally across the wires in pairs at intervals of about 18" (45cm), any others being cut out. Pinch out the tips of the sideshoots. Continue with this process until the framework is covered. Fruiting spurs will develop and hang downwards from the sideshoots and these should be treated in the same way as on wall-trained plants.

In both pruning systems, wayward shoots that arise elsewhere on the plants should be cut out promptly.

Harvesting

Pick the fruits in the autumn when they are slightly soft to the touch and snap easily from the stalk. They store well and will keep at room temperature for 2 weeks and for about 3 months in a refrigerator. Harvest all the fruit whether ripe or not before the first frosts and ripen them gradually in the warmth indoors.

Pests and Diseases

Aphids, Red Spider Mites and caterpillars are usually the biggest problems. (See the pests and diseases sections for prevention's and cures).