Hardy kiwi (Actinidia arguta and Actinidia kolomikta) is the cold-hardy cousin of the vine that produces the familiar kiwi fruit sold at grocery stores. The latter is the species Actinidia deliciosa and is hardy only to USDA plant hardiness zone 8. Hardy kiwi is much more cold-tolerant and can be grown in zones 3, 4, or 5 (and up to 8 or 9), depending on the variety. Like its warm-weather cousin, hardy kiwi also produces a sweet edible fruit, but the hardy version is smaller (about the size of a large grape) and can be eaten whole, without peeling.
While its fruit is delicious, hardy kiwi is grown in landscapes primarily for its attractive heart-shaped foliage. It is a fast-growing, vigorous vine but is rarely invasive in the way that other fast-growing vining plants can be. Kiwis are climbers of the "twining" type that grow well on trellises, fences, pergolas, and other structures. However, the vines can also overcome shrubs and small trees if left unchecked.
Hardy kiwi flowers in the spring and produces fruit in the fall. Most varieties are dioecious (separate male and female plants), and females must be pollinated by a male in order to fruit. However, there is one self-pollinating variety that can fruit on its own.
Hardy kiwi should be planted in spring after all danger of frost has passed. The vine itself is fast-growing and will create landscape impact in its first season, but you can expect to wait at least three years before looking for fruit to harvest.
|Botanical Name||Actinidia arguta, Actinidia kolomikta|
|Common Name||Hardy kiwi, hardy kiwi vine|
|Plant Type||Perennial fruiting vine|
|Mature Size||10 to 30 feet long|
|Sun Exposure||Full sun to part shade|
|Soil Type||Well-drained loam|
|Soil pH||5.5 to 7.0 (acidic to neutral)|
|Flower Color||Green, white|
|Hardiness Zones||3 to 9 (USDA), varies by variety|
|Native Area||China, East Asia|
Hardy Kiwi Vine Care
Hardy kiwi vines are native to eastern Asia, but they grow well almost anywhere with proper care and sufficient sun. Whether you're growing them for foliage, shade, or fruit (or all three), it's best to train the vines on a sturdy support structure, such as a trellis, arbor, pergola, or fence. They can be trained to form a broad canopy or to branch out horizontally in espalier form.
If you're growing kiwi vines for their fruit, be sure to plant both male and female plants for pollination, or choose a self-pollinating plant. You need at least one male for every eight female plants. Keep in mind that the vines typically don't fruit for at least three years, while some plants take five to nine years to begin fruiting.
Hardy kiwi vines can tolerate a range of light conditions from sun to shade, but greater exposure to the sun often results in superior color in the varieties with variegated leaves.
Water sufficiently to keep the soil moist, especially after planting the vine. Weekly watering is recommended during dry weather. Mature plants may need no additional watering beyond rainfall, depending on the climate.
Plant kiwi vines in a loamy, well-drained soil. Some experts advise that planting in poorer soil may control the fast growth of the plant.
Temperature and Humidity
Hardy kiwi can survive winter in most areas, but it is susceptible to damage from late frosts. For this reason, choose a planting site that is not in a frost pocket or subject to particularly cold wind in spring.
This vigorous vine requires little in the way of feeding. A light layer of compost over the root area provides all the nutrients necessary. If you do want to feed the vine, use a slow-release or organic fertilizer, and apply it carefully to prevent fertilizer burn.
Varieties of Hardy Kiwi
- Actinidia arguta 'Anananzaya' is a vigorous grower with very sweet fruit; also called 'Anna'; it is hardy to zone 5.
- Actinidia kolomikta 'Arctic Beauty' has distinctive foliage that is variegated with attractive patches of white. It is hardy to zone 4.
- Actinidia arguta 'Issai' is the only hardy kiwi that is self-pollinating and does not need a separate male for pollination. It is hardy to zone 5.
- Actinidia purpurea x melanandra ‘Ken’s Red’ produces reddish-purple fruit and is hardy to zone 4.
With 'Arctic Beauty,' the male plants typically have better leaf variegation than the female plants. This variety opens in the spring with green leaves that soon pick up splotches of white. As an encore, some leaves then develop pink tips. When growing hardy kiwi for appearance (not fruit), most people plant only the male vines.
It's best to prune hardy kiwi vines in winter, to promote fruit production. The first year after planting, select the most vigorous shoot that is straight, designating it as the permanent trunk. Cut back other shoots so as to concentrate vigor in the trunk. In subsequent winters, cut back each stem to 8 to 10 buds. In addition, prune as needed during summer to remove any excessively long shoots. There also may be more pruning techniques specific to the trellising method used.
The fruit from hardy kiwi is normally harvested in early fall when the fruit is still hard to the touch but the seeds are black. They should be eaten immediately or can be stored in the refrigerator for a few weeks.
Landscape Uses for Hardy Kiwi
Trained up a supporting structure, kiwi vines can function as privacy screens for the summer. However, since they lose their leaves in fall, kiwis are not useful for year-round privacy screening. But the beauty of their variegated leaves gives you another reason to train them on a supporting structure: namely, to display them most effectively as specimen plants. The shade tolerance of kiwi plants makes them an option for shady areas where many other vines would not perform well.
Although these vines don't grow as large as some others, they are very fast-growing and have been known to overwhelm shrubs and small trees if not supervised and controlled with regular pruning.
Common Pests and Diseases
There are very few serious pest or disease problems with hardy kiwi vine. Most issues have to do with its growth habits or damage from wildlife. Leaves and flowers can be damaged by frost, and a late spring frost on flowers usually means no fruit for that year. Other diseases include: Botrytis rot, Phytophthora crown and root rot, and Sclerotinia blight.
Keep an eye out for critters: Japanese beetles, leaf rollers, root-knot nematodes, snails, thrips, and two-spotted spider mites. Rabbits may eat the branches in winter. Deer, cats, and gophers may eat the leaves. Birds and other animals often target the fruit as it ripens.