Hardy kiwi vine refers to one of two plant species within the Actinidia genus, which also includes the plant that produces the delicious kiwifruit sold in grocery stores (Actinidia deliciosa). The hardy kiwi vines used for landscape purposes include Actinidia arguta and one variety of Actinidia kolomikta, named 'Arctic Beauty'. Although these plants do produce edible berries, the appeal of the plant lies in the attractive heart-shaped foliage, which in the case of 'Arctic Beauty' is variegated with white patches. It is a fast-growing, vigorous vine, but is rarely invasive in the way that other fast-growing vining plants can be.
Hardy kiwi is a fast-growing deciduous woody vine that generally tops out at 20 to 30 feet. Actinidia arguta is more vigorous and may achieve greater heights (up to 30 feet), and is hardy to USDA hardiness zone 3. Actinidia kolomikta 'Arctic Beauty' is a similar plant but has startling, unique foliage that is variegated with attractive patches of white. 'Arctic Beauty' is a slightly smaller plant, topping out at about 20 feet; it is hardy to USDA hardiness zone 4.
Both plants flower with white or greenish-white blossoms in April to May, and edible fruits about 1 inch in diameter appear in fall. These species are dioecious (separate male and female plants), and with Actinidia kolomikta 'Arctic Beauty,' it is reported that the male plants have better leaf variegation than the female plants. 'Arctic Beauty' opens in the spring with green leaves that soon pick up splotches of white. As an encore, some leaves then develop pink tips. If growing the plant for appearance, most people plant only the male vines. If growing for the fruit, it is recommended to plant one male for every four or five female plants.
Kiwis are climbers of the "twining" type that grow well on trellises, but the vines can also overcome shrubs and small trees if left unchecked.
Both species come from the temperate regions of eastern Asia, where they are found in woodlands, mountain forests, stream banks, and other moist locations in China and Japan. Plant taxonomy classifies the hardy kiwis as Actinidia kolomikta or Actinidia arguta. Both are distinct from the plant that produces the kiwifruit sold in grocery stores (Actinidia deliciosa, which is hardy only up to zone 8), although the smaller fruit is similar in taste. The variegated form of hardy kiwi vine is a cultivar of Actinidia kolomikta, 'Arctic Beauty.' In the U.S., hardy kiwi vines are reliably hardy in USDA hardiness zones 3 to 8.
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 don't 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.
Increasingly, hardy kiwi vine is grown by gardeners seeking to use the grape-sized fruits for preserves and recipes. The vines generally must mature for 3 years or so before good fruit is produced.
Growing Hardy Kiwi Vine
Plant kiwi vines in a loamy, well-drained soil. Be sure to provide adequate water. The plants 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. Some experts advise that planting in poorer soil may control the fast growth of the plant.
For optimal display, kiwi vines are best grown on supporting structures, such as sturdy trellises (mature plants are heavy), arbors, pergolas, or wooden fences. According to the University of Minnesota Extension, pruning (to be performed in winter) should focus on selecting the "straightest and most vigorous" shoot a year after planting and treating that selected shoot as a permanent trunk. Prune out other shoots, so as to concentrate vigor in the one shoot. The Missouri Botanical Garden observes that hardy kiwi needs regular pruning, including an annual winter pruning of each stem back to 8 to 10 buds, along with a summer pruning to remove any excessively long shoots.
This vigorous vine requires little in the way of feeding. A light layer of compost over the root area provides all the nutrients necessary.
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:
- Spring's variegation may fade by summer, leaving a relatively unattractive vine.
- Plants may require a waiting period before the variegation appears.
- Leaves may be damaged by frost.
- Rabbits may eat the branches in winter.
- Cats may eat the leaves.
- Growth may be too fast; plants can overwhelm shrubs and small trees if not kept in check.