KiwiActinidia deliciosa

The kiwi is dioecious: except for self-fertile varieties, you need a female that carries the fruit and a male that supplies the pollen. Hayward, the standard female, flowers late, at the end of May, and goes with Tomuri or Atlas, late males; Bruno and Abbott, earlier, match Matua. One male pollinates five to eight females within a radius of 5 m. The self-fertile Jenny and Solissimo produce on their own, but with smaller fruit, and always do better alongside a male. The kiwiberry, Actinidia arguta, hardier and earlier, comes as the females Geneva, Ken's Red or Weiki, with an arguta male, and as the self-fertile Issai.

The climber wants sun, a south- or west-facing wall, and above all shelter from the wind that tears its large leaves and snaps the young shoots. Its May flowers have nothing to fear from frost, but its April shoots are scorched at -1 °C: avoid frost pockets. Provide the permanent support before planting, because a mature kiwi weighs several hundred kilos: posts 10 cm square set 2 m high, every 4 m, joined by three 3 mm steel wires, or a pergola in structural timber. Against a wall, wires on eyes set 15 cm out are enough. Space at 3 to 4 m.

The kiwi wants a deep, rich, moist and slightly acid soil, pH 5.5 to 6.5: it goes chlorotic on chalky soil and rots in waterlogged ground. Dig a pit 80 cm square and 60 cm deep, loosen the bottom and work in three spadefuls of mature compost, one of leaf mould or composted bark, and a handful of hoof and horn. On heavy soil, plant on a 20 cm mound with coarse sand; on chalky soil, be generous with pine bark and plan on a permanent acid mulch. The kiwi likes neither salt nor chlorine: alongside a salted road, choose another spot.

Plant preferably in April, after the hard frosts, a container-grown plant of two or three years whose sex is guaranteed by the label; seedlings do not fruit for seven years and their sex stays unknown. Soak the rootball, tease it out, set the crown at soil level, male in the middle of the group of females. Fill in, firm, water with 20 litres, mulch over a metre. Keep a single stem only, cut back to 30 cm above a vigorous bud, tied to a vertical stake that will lead it up to the wires: this will be the trunk. Planting in October is possible in a very sheltered position, with protection at the base.

The Hayward kiwi is too vigorous for a pot; keep the container for the self-fertile Jenny or Solissimo, or better still for the Issai kiwiberry, more compact and ready to produce from the third year. Take a container of at least 80 litres, a mix of garden soil, potting compost and garden compost over a drainage bed, and a sturdy 1.8 m trellis. The weak point is water: the large leaves demand daily watering in summer, failing which they scorch at the edges. Feed in April and June, prune short in January and in summer, repot every three years. Expect a few dozen fruits per container.

The first is to buy a single kiwi that is not self-fertile, or two females, and to wait ten years for fruit that will never come. The second is to under-size the support: a pergola built of 3 cm battens collapses in the fifth year. Many people plant on chalky or waterlogged soil, where the climber yellows and stands still, or in full wind, where it tears itself. You also see kiwis left unpruned, an impenetrable bush that flowers little. Finally, letting a young shoot run in April without a fleece, then watching it blacken in one frosty night, costs a year; keep the fleece to hand until the Ice Saints.

The kiwi is the thirstiest plant in the fruit garden: its large leaves transpire enormously and its fleshy roots are shallow. For the first five years, water twice a week in dry weather, 20 to 30 litres each time, from April to September; once mature, a generous weekly watering in summer is still needed, especially against a wall. A shortage of water shows quickly: leaves hanging at midday, scorched edges, small fruit. But standing water kills the roots: water slowly on drained soil. A drip line under the mulch, two hours every other day in July, settles the question.

A thick 10 cm mulch of wood chippings, dead leaves or pine bark, over 1.5 m across, keeps the essential moisture and maintains the acidity. The kiwi is hungry: in March, spread a barrowload of mature compost for two plants, topped up with a handful of hoof and horn; in June, diluted nettle liquid stimulates growth. Avoid concentrated mineral fertilisers and fresh manure, which burn the roots, and any feeding after July, which would stop the wood ripening before winter. On chalky soil, a handful of granular sulphur in spring and a chelated iron dressing in case of chlorosis.

In the first year, lead a single stem up the stake to the wires, pinching out every lateral; once it reaches 1.8 m, cut it back just above the wire: two opposite shoots will form the horizontal arms, laid along the central wire. In the second and third years, let fruiting laterals grow on these arms every 30 to 40 cm, tied in on the outer wires. From then on, every January, outside frosty spells and before the bleeding starts, prune each lateral that has fruited to three or four buds beyond the last fruit, and renew exhausted laterals every three years by cutting them back to a new shoot near the arm. The fruit is borne on the first buds of the year's shoots, which come from one-year-old wood.

Without summer pruning, a kiwi produces 5 m of stems that wind round everything. From June to August, pinch the fruiting shoots five or six leaves beyond the last fruit, remove the water shoots that spring from the trunk and the arms, and cut the stems that twist round the wires: coiled stems strangle the branches and hold damp. Thin in June to one fruit every 10 cm if the crop is excessive, and the fruit left will double in size. Open up the foliage around the clusters of fruit so that the sun colours the flesh and builds the sugar. Tie in the new laterals with soft ties.

The mature wood of the kiwi withstands -15 °C, but the young spring shoots freeze at -1 °C and the crown of a young plant suffers below -8 °C. For the first three winters, earth up the base by 30 cm with soil or dry straw and wrap the trunk in hessian. In April, keep a winter fleece ready to lay over the shoots in the evening on a clear night. The kiwi has almost no diseases in Belgium; PSA bacterial canker, feared in commercial orchards, is prevented by avoiding wounds in damp weather. Cats like to roll in the scented roots of young plants: wire netting at the base protects them. Birds take no interest in the fruit.

In January, prune outside frosty spells. In March, compost, mulch, remove the winter protection gradually. In April, watch for frosts and fleece the young shoots, remove the water shoots on the trunk. In May, the creamy white flowering perfumes the garden; let the bees do their work, spray nothing. In June, thin, pinch, begin the generous watering. In July-August, water, pinch again, cut the stems that coil round. In September, stop all feeding, pick the kiwiberries. In late October or November, harvest the kiwis before the hard frosts, then gather up the leaves and earth up the base of young plants again.

The kiwi is picked firm, all at once, in late October or November, as soon as a frost of -2 °C is forecast or the leaves start to yellow; a fruit frozen on the plant goes soft and rots. Cut a test fruit open: black seeds and bright green flesh mean the moment has come, and the sugar will go on rising in the cellar. Detach each fruit with a sharp upward tug, without pulling off the stalk, and set it down without knocking it. Store in shallow crates in a cold, airy cellar, away from apples, which would ripen them too quickly; bring the fruit you mean to eat into the kitchen ten days ahead, with an apple to speed things up.