Shrub · Actinidiaceae
Hardy Kiwi
Actinidia arguta
A cold-hardy vine hung with smooth-skinned, grape-sized berries eaten whole, needing no peel.
Full sun
Every 5–7 days
USDA 3–8
25–30 ft · 7.6–9.1 m
Overview
Hardy kiwi carries the flavor of the fuzzy grocery kiwi in a berry no bigger than a grape. Each fruit wears smooth, hairless skin that slips clean between your fingers, and the flesh inside is sweet and aromatic, popped whole into the mouth. For all that tender fruit, the vine takes cold that would blacken a regular kiwi, holding firm through winters down to -29°F (-34°C).
The vine itself is a heavy, muscular climber. Its long canes can stretch 30 feet (about 9 meters) in a run and thicken until they weigh enough to bow a slight support, so they want a strong arbor or T-bar trellis to grip from the start. That same reaching, twining habit is why it carries an invasive flag in parts of the northeastern US, so keep it back from wild ground and check the local rules before it goes in.
In late spring the canes open small, fragrant greenish-white flowers, and this is where the plant's one quirk shows. Hardy kiwi is dioecious, so those male and female blooms sit on separate plants, and only a pollinated female flower will fatten into a berry. Give it full sun, shelter, a strong frame to climb, and a few years, and the stems hang thick with fruit from late summer on.
Care
The short version: full sun and rich, well-drained soil kept evenly moist, on a trellis heavy enough to carry a thick, fruit-laden vine. Set a male among the females, cut hard in winter, and give the canes a few years to fatten before the first real crop.
Light
Hardy kiwi colors and sweetens its berries best in full sun, which also drives the heavy leafy growth. It will hold in partial shade, though the fruit comes lighter. A warm, sheltered spot also shields the soft early shoots from late frost.
Water
Keep the soil evenly moist, above all while the vine is rooting in and while the berries are swelling, watering roughly every 5 to 7 days. Water deeply so it reaches down to the roots. Drainage rules everything else, since sodden ground rots the roots brown and soft.
Soil
Give it fertile, well-drained loam dark with organic matter, though it takes clay, loam, or sand too. It leans to the acidic side, around pH 5.0 to 6.5. Because drainage counts more than texture, dig in compost and skip any low spot where water stands.
Temperature
This is a genuinely cold-hardy vine, its canes riding out winter lows near -29°F (-34°C) and summer heat up to about 86°F (30°C). The weak point is timing, not raw cold, since a late spring frost blackens the tender new shoots once the vine has leafed out.
Humidity
Ordinary outdoor humidity in the 40% to 70% range suits it well, so there is no figure to chase. Open airflow through the canes matters more, keeping the dense leafy canopy from staying wet.
Feeding
Feed a balanced complete fertilizer through spring and early summer while the vine is in hard growth. Keep the nitrogen light. Too much floods the plant into leaf and cane at the expense of the fruit, the last thing you want on so vigorous a vine.
Pruning
Hardy kiwi needs real cutting to stay fruitful and in bounds. In winter, shorten each fruiting stem back to 8 to 10 buds. Come summer, cut the long, whippy shoots again and tie the whole vine tight against its trellis.
Repotting
This vine grows in the ground on a trellis rather than in a pot, so it is rarely repotted. If you do start one in a container, shift it on before the roots coil the sides, stall, or dry out unusually fast, then set it into the ground.
Size & spacing
Plan for a big, reaching vine. Its canes run 25 to 30 feet (7.5 to 9 m) long and spread 7 to 20 feet (2.1 to 6 m) wide, so give it a sturdy, dedicated frame and plenty of room to stretch.
When to plant
Hardy kiwi tracks the seasons. Start seed in late winter after a long cold spell, set young plants out in spring once hard frost has passed, then watch the canes open fragrant flowers around June and hang grape-sized fruit that ripens from late summer into fall.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Late winter (Feb-Mar) after 30-60 days cold stratification of seed
- Plant: Spring, after danger of hard frost has passed
- Harvest: Fragrant greenish-white flowers in late spring (around June); grape-sized fruit ripens late summer into fall (Sep-Oct)
Hardiness
USDA hardiness zones: 3–8
Temperature: down to -40°C
Troubleshooting
Most of what goes wrong on a hardy kiwi shows in one of three ways: bare fruitless stems, limp yellow leaves over sodden roots, or blackened spring shoots. The close-up signs below tell them apart. Read the plant, then act before the season slips away.
Limp, yellowing leaves over roots gone brown and soft
Leaves that hang limp and fade from green to yellow, over ground that never dries, point straight at root rot taking hold where wet soil has choked the air from the root zone. Lift a root and the firm, pale white of healthy tissue has gone brown and soft to the touch, mushing between your fingers. Water less, open up the drainage, or lift the vine onto a raised, free-draining bed before the browning creeps up the crown.
Fix:
- Improve drainage or move to a raised, well-drained site
- Reduce watering frequency
Dense green growth with bare stems where fruit should hang
The vine can drape a trellis in leaf and still leave every stem bare, because hardy kiwi is dioecious and a female flower cannot swell into a berry without pollen from a male plant close by. Age shows too, since a young vine often spends 3 to 5 years thickening its canes before it fruits at all. Set out one male for every 6 to 8 females, leave the small flowers open for bees to reach, and let the vine bulk up.
Fix:
- Plant at least one male per 6-8 females
- Be patient; vines fruit only after several years of growth
- Ensure bees and other pollinators can reach the flowers
Tender new shoots turned black and drooping
Hardy kiwi pushes its soft new shoots out early, so a single late spring frost can turn that fresh green to black overnight, leaving the tips wilted and folded over by morning. The blackened growth looks dead because it is, yet the vine usually resprouts once you cut the ruined shoots back to live wood. Plant it clear of low frost pockets, and drape a cover over the new growth whenever a late chill is forecast.
Fix:
- Prune out blackened growth; vines usually resprout
- Cover or protect vines when late frost threatens
Toxicity
Good news for pet owners: hardy kiwi is not toxic to cats, dogs, or anyone else. The smooth berries are grown to be eaten, and the leaves and stems will not poison an animal that nibbles them. The one quirk worth knowing is that cats may be drawn to the foliage the way they are to catnip or silver vine, which is harmless attraction rather than any danger.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Hardy kiwi is safe for cats, and the smooth berries carry no poison. The pull runs the other way, since like silver vine the leaves can act as a catnip-like lure, so a cat may press and roll against the vine or gnaw a slim young stem, which leaves nothing behind but a chewed shoot.
Dogs None
A dog is safe around this vine. A few of the small, grape-sized berries slip down without trouble, though a whole mouthful of any unfamiliar fruit may bring a brief bout of loose stool.
Horses Safe
Horses can graze right up against the vine unharmed, since neither the broad leaves nor the smooth fruit holds anything toxic to them.
Rabbits Safe
Rabbits are safe with hardy kiwi, and a bite of the soft, juicy fruit makes a fine occasional treat, though the bulk of their diet should stay hay and greens rather than sweet kiwi.
Livestock Safe
Cattle, goats, and sheep can browse the leaves and windfall fruit with no risk of poisoning from this plant.
Birds Safe
Birds strip the ripe berries unharmed, and as they feed they carry the seed off, part of why the vine seeds itself so freely.
People Safe
The smooth, thin-skinned fruit is grown to be eaten whole like a grape, no peeling needed, and it is perfectly safe for children and adults alike.
Fruit is safe if a pet nibbles a few; very large amounts of any novel fruit may cause mild, temporary stomach upset.
Varieties
A handful of named cultivars cover most home plantings, split between the fruiting females and the males grown purely to shed pollen. These are the ones worth knowing by name.
Ananasnaya (Anna)
A popular, heavy-cropping female loaded with sweet, aromatic fruit at harvest.
Issai
A partly self-fertile female that can swell a little fruit even with no separate male vine beside it.
Geneva
An early-ripening female that colors up its crop well ahead of the others and brings the harvest forward.
Meader Male
A male pollenizer that sets no berries of its own and lives only to shed pollen onto the females around it.
Companions
Hardy kiwi grows best next to a male pollenizer and the bees that work its flowers, and worst when left to climb into trees and shrubs it can smother.
Plant near
Male Actinidia arguta cultivar: Required pollenizer; without a male nearby, female vines set no fruit.
Pollinator-attracting flowers: Bees and other pollinators improve fruit set on the kiwi flowers.
Keep apart
Trees and shrubs: The vigorous vine can climb and smother woody plants; keep it on a dedicated sturdy trellis.
How to propagate
Hardy kiwi can be multiplied several ways, but only some carry the sex and quality of the parent. Pick the method that fits whether you need a known cultivar or simply more plants.
Stem cuttingsModerate
Softwood cuttings in early to mid summer · About 6-10 weeks to root
A softwood cutting, the green and pliable growth of the season, copies a named male or female true to type. Taken in early to mid summer, it pushes fresh white roots in about 6 to 10 weeks, and starting from a known sex is what secures fruit later.
SeedModerate
Sow in late winter after 30-60 days of cold stratification · Germinates in weeks; years to reach fruiting
Seed is a mixed bag. Sown in late winter after 30 to 60 days of cold stratification, the tiny seedlings break the surface within weeks, but they grow up uneven and of unknown sex, hidden until the first flowers open years on, so male and female stay indistinguishable until then.
LayeringEasy
Spring to summer · Roots within one season
Layering is the simplest trick. Bend a low, flexible cane down and pin it against the soil any time from spring through summer, and it roots within a single season along the buried length, after which you cut it free and lift the new plant.
GraftingDemanding
Late winter to early spring · Takes within one growing season
Grafting is the exacting one, joining a chosen cultivar to vigorous rootstock so the two knit into a single stem. Worked in late winter to early spring, a clean union takes within one growing season.
Myths
The berries are poisonous to pets, since cats react to the foliage the way they do to catnip.
Cats truly are drawn to Actinidia foliage, since silver vine shares the genus, but that fascination with the leaves is nothing like poisoning. The smooth-skinned, grape-sized fruit is edible and safe for cats and dogs alike.
One hardy kiwi vine sets fruit with no other plant nearby.
Most hardy kiwis are dioecious, so a male and a female must grow together, about one male for every 6 to 8 females, before a single berry forms. The exception is a partly self-fertile type like Issai, which swells at least a little fruit on its own.
The berries must be peeled before eating, much like the fuzzy kiwifruit.
Its skin is smooth and hairless to the touch, with none of the fuzz of a grocery kiwi. You eat the whole berry like a grape, skin and all.