Hardy kiwi

Hardy kiwi: how do you recognise it?

Habit

Vigorous twining climber of 6–10 m that winds itself around wires, posts and branches.

Leaf

Alternate, 8–12 cm, ovate to broadly elliptic with a pointed tip, finely and sharply toothed, glossy and hairless; leaf stalk often red.

Stems

Smooth, brown twining stems (not hairy) with chambered pith; old stems with peeling bark.

Flower

White, fragrant flowers (2 cm) with dark anthers, May–June; usually separate male and female plants.

Fruit

Smooth, green (red in some varieties) fruits of 2–3 cm in clusters, September–October; you eat them skin and all.

Difference from kiwi fruit

Kiwi fruit has larger, round leaves on stalks with reddish-brown hairs, and large, hairy kiwis.

Difference from grapevine

Grapevine has lobed leaves, tendrils and grapes in bunches.

Flowering: June · Harvest and fruit: September–October · Pruning: July and December–February

Identify by feature: Twining climbers

Looks like it, but isn’t

• Kiwi fruit Actinidia deliciosa: larger, round leaves on stalks with reddish-brown hairs, and large, hairy kiwis. Difference from kiwi fruit
• Grapevine Vitis vinifera: lobed leaves, tendrils and grapes in bunches. Difference from grapevine

Why grow it?

• Sweet mini-kiwis that you eat straight from the plant, without peeling.
• Much hardier than the kiwi: it tolerates down to −25 °C.
• Fast, dense green cover for a pergola, fence or sturdy wire.
• White, fragrant flowers in May–June.

Hardy kiwi: where does it grow best?

• Sun or partial shade; in sun the fruit ripens sweeter.
• Humus-rich, well-drained soil that doesn’t dry out; no wet roots.
• Sturdy support is essential: a pergola, fence or tensioned wires, as a mature plant is heavy.
• Not against a tree: it winds around trunks and branches and can strangle a young tree.

Light

Sun or partial shade

Legal basis

Any garden soil

Moisture

Normal

Size

8 m tall, 4 m wide

Hardiness

Throughout Belgium, no protection needed

Goes well with

• Kiwi fruit: Its larger, less hardy relative: together on a pergola you have small and large kiwis.
• Grapevine: Grows on the same pergola and is pruned the same way.
• Japanese wineberry: Another unusual berry for the fruit garden, with sweet red fruits in summer.

Good and bad companions

Best kept away from

• Twines around young trees and shrubs and can strangle them: hawthorn, goat willow, japanese cherry, judas tree, chusan palm, olive tree

Hardy kiwi: when and how to plant it?

1. Plant in spring (April–May), after the worst frosts.
2. Buy a female plant (such as ‘Weiki’) and a male, or the self-fertile variety ‘Issai’. One male is enough for six to eight females.
3. Space the plants 3–4 m apart, with the male near the females.
4. Plant them at the same depth as in the pot, guide them to the support with a cane and water well.

Care

Watering

Regularly in dry summers: the shallow roots dry out quickly.

Mulching

A layer of compost or straw keeps the roots cool and moist.

Tying in

Guide young shoots in the right direction and tie them in before they tangle.

Harvest

Pick in September–October when the fruits feel soft; fruits picked firm ripen within a few days. They don’t all ripen at once.

Tip: Pick some of the clusters while still firm and keep them in the fridge: that way you have mini-kiwis for weeks, letting a handful ripen on the kitchen worktop for a day each time.

Hardy kiwi: when to prune it?

Pruning months: July and December–February.

When: While dormant in winter (December–February), and the long stems in July.

How:

• Prune like a grapevine: keep a sturdy framework and in winter cut the side shoots that have fruited back to 2–3 buds.
• In July, shorten the stems beyond the fruit, and remove long stems that bear nothing.
• Also cut away shoots that twine towards trees, gutters or roof tiles.

Caution: Don’t prune in spring: it will bleed.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Cuttings

In summer, take semi-ripe cuttings from a female or a male plant: that way you know for sure which sex the new plant is.

Layering

Lay a long stem on the ground and cover a section with soil; a year later, cut it free with its roots.

Hardy kiwi: how does it get through the winter?

Hardy throughout Belgium: no protection needed.

• Very hardy: it tolerates down to −25 °C.
• Late frosts in April–May kill the young shoots and flower buds: cover a small plant with fleece when frost threatens.

Diseases and pests

• No fruit: No male plant nearby, a plant that is too young, or frosted flower buds. Check that you have a female and a male plant, or choose ‘Issai’.
• Late frost: Brown, limp young shoots after a frosty night in spring. Cut them off; the plant will reshoot, but flowers less that year.
• Too rampant: Long stems overrun pergola, gutter or nearby trees. Prune in winter and in July.
• Root rot: Yellow leaves and dying stems in soil that stays wet for long. Plant in a well-drained spot.

Through the year

• January: Winter pruning: cut fruited side shoots back to 2–3 buds.
• February: Finish winter pruning, before the sap rises.
• April: Planting; protect young shoots from night frost.
• May: Flowering begins; tie in new shoots.
• June: Water in dry spells; mulch.
• July: Summer pruning: shorten stems beyond the fruit.
• September: Harvest: pick the soft fruits.
• October: Pick the last fruits, before the frost.
• December: Winter pruning can begin.

What can you use it for?

Food and drink

Sweet, smooth mini-kiwis that you eat skin and all; harvest in September–October.

Garden and landscape

Vigorous, very hardy climber for a pergola, fence or sturdy wire.

Caution: You need a female and a male plant, unless you choose a self-fertile variety such as ‘Issai’. One male is enough for six to eight females.

Edible and useful

Fruit (September–October)

Pick kiwi berries in September–October, when the fruits are full-sized and the seeds are dark (brown to black) when you cut one open; the fruit is then still firm and not yet sweet. They ripen after picking: leave them for 1 to 2 weeks at room temperature, until they give slightly. They are then sweet and aromatic. If you prefer to let them ripen on the plant, pick them as soon as they begin to soften, but bring everything in before the first hard night frost, because frost damages the fruit. Put an apple or banana in the bag to speed up ripening. You eat them whole, skin and all: they are smooth, without any fuzz.

Storing

Firm kiwi berries keep for a few weeks in the fridge; then leave them to ripen at room temperature. Eat ripe fruit within a few days. You can also freeze them: lay the whole fruits in a single layer on a tray, then bag them up. Jam keeps for a year and dried kiwi berries for six months.

Caution: Kiwi is a well-known allergen: stop eating if you get itching, tingling or swelling in your mouth or throat. Eat only the fruit, not the leaves or stems. Do not confuse the green fruits with the green, unripe berries of other climbers, such as woody nightshade or bryony, which are poisonous: kiwi berries are smooth, green, oblong fruits of 2–3 cm with green flesh full of tiny black seeds. Eating many raw, still hard kiwi berries at once can make your mouth feel prickly. Throw away mouldy fruit. Wash the fruit, do not pick from sprayed plants and never eat anything you have not identified with certainty.

Eating and using is at your own risk: see the terms of use.

Recipes

• Kiwi berry jam (Jam · ± 4 jars of 250 ml · 40 min + 30 min standing)
• Kiwi berry sorbet (Dish · 4 servings · 15 min + 4 hrs freezing)
• Dried kiwi berries (Dried · ± 100 g dried fruit · 8–12 hrs)
• Kiwi berry salsa with red onion and lime (Dish · 4 servings (with fish or chicken) · 15 min)

Did you know?

• Much hardier than the kiwi: it tolerates down to −25 °C. Only late frosts can damage the young shoots in spring.
• Arguta means ‘sharply toothed’, after the finely and sharply serrated leaf edge.
• In shops it is also sold as kiwiberry or mini kiwi, and in France as kiwaï.