What is Hardy Kiwi? The Perennial Kiwi for Cold Climate Gardens

  • Post category:Plant Focus
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What is a hardy kiwi? What does it taste like? Should you plant some in your garden? Read on to find out.

Hardy kiwi is a vigorously growing perennial vine in the Actinidia family. It’s hardy to USDA zones 3-9, depending on the variety. The fruit is a small grape-sized kiwi, which grows in clusters. They can be eaten whole, without peeling. The fruit is sweet and tastes similar to a regular kiwi.

This plant is truly wonderful. There are a rare few magical fruiting plants that allow us colder-climate gardeners to feel like we’re in the tropics, where magnificently sweet fruit and lush foliage is abundant. Hardy kiwi is one of these amazing plants! 

Below I’ll talk about what the plant is like, growing, harvesting, and eating it, permaculture adaptations, and cultivar information. 

What is the Hardy Kiwi Like?

Hardy kiwi is a vining plant, related to the standard kiwi (Actinidia). It originates in East Asia, including Japan, Korea, northern China, and eastern Russia. It grows very vigorously, naturally climbing up trees and growing a great big mass of leaves. It can grow to a mass of 10 to 30 feet. When cultivated, it requires a strong trellis, such as a strong wooden one, that can hold up the weight of this vigorous plant. This makes it ideal for a garden arbor / archway.

It has reddish vines with vibrant green leaves. The fruits are small, growing in clusters like grapes. The fruit is ripe and ready to eat in the fall. It will take a few years for a plant to mature enough to make fruit

The vine is quite cold-hardy, as the name suggests. But the fruit is not, and that can sometimes be a problem. To alleviate this, the fruit can be harvested before it’s fully ripe, if a frost is predicted. Fruit that does not ripen on the vine may not be as sweet as vine-ripened little kiwis, but they can be stored in the fridge for a couple of months, and then taken out a few days before you want to eat them (to let them finish ripening). 

The plant is dioecious, meaning that each individual plant is either male or female. For this reason, you need to make sure you have both male and female plants to get fruit! One male is enough to pollinate several females, comfortably 6 to 8 of them. But yes, if you want to be eating hardy kiwis, you need to make sure you get plants from both sexes. The males will serve to pollinate, but will not make fruit. So it is ideally to have just a few of them to pollinate many female plants.  One variety, “Issai”, is self-fertile, and will pollinate itself, so if you can only grow one plant, consider this variety. But it’s the only known variety that shows this behavior.

The plant itself is quite beautiful, and for that reason has a lot of ornamental value. With abundant white flowers blooming in the spring, it puts on quite a show. Consider placing hardy kiwi plants by your garden’s arbor entranceway, or building a trellis against a south-facing wall, for a spectacular effect.

By Qwert1234 – Qwert1234's file, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=7082332

The plant itself likes well-drained, but also moist soils, in the 5.5 to 7 ph range (acidic to neutral). Mulch will help keep the plant’s soil moist. But if your soil is too clay-ey and doesn’t drain well, consider planting hardy kiwi on a mound or raised bed, to help it keep its roots out of the muck.

Is it good to eat?

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Hardy kiwi is GREAT to eat! They are very sweet and taste much like a kiwi. Let me repeat, that you don’t need to peel them, you can just eat them whole, like a little grape. 

Eaten whole is perhaps the best way to eat them, though they can also be made into jams, using any basic jam recipe. Try putting them in a salad, or in yogurt! Another idea is to include them in a fruit tart. Be creative! One of the most enjoyable parts of gardening is finding creative ways to enjoy the abundant produce you’ve grown yourself.

Hardy kiwi has an amazing nutritional profile, boasting more vitamin C than oranges, more vitamin E than avocados, and more potassium than a banana!(*https://www.oregonlive.com/foodday/2008/09/how_do_you_use_hardy_kiwis_jus.html)

If that’s not enough for you, young hardy kiwi leaves are also edible! They are used as a vegetable in Korea, and can be found sold in some korean markets as darae-sun, meaning the young leaves of hardy kiwi. 

By Sakateka – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=76689416

How Do I Care for my Hardy Kiwi Vine?

Hardy kiwi is a heavy feeder. An application of compost or fertilizer in the spring will help. The most common problem that hardy kiwi vines get is crown rot and root rot. A well-drained soil will mitigate this problem. Make sure you don’t put mulch right up to the base of the plant, give it a little breathing room, to allow for adequate air flow. 

If your soil is very clay-ey, or otherwise prone to hold water, consider mounding up a raised bed. This typically will help any plant which doesn’t like wet feet, and hardy kiwi is no exception. Hardy kiwi also likes to be well watered, so make sure to water it as needed. Mulch always helps to keep soil moist.

Tip: Make sure your trellis is sufficiently strong. Hardy kiwis have been known to climb up 100-foot tall trees, and can grow up to 100lbs of fruit on a single vine!

Harvesting: How To Know When Hardy Kiwi Ready

Different varieties are ready at different times in different climates. But you can expect to start harvesting generally in August. Pick a few kiwis for a test. They will still be hard, but can be left sitting out to ripen after harvest. When the flesh is soft and seeds are black, they should be ready. They are generally harvested before ripening, and stored in an air-tight bag in the fridge. Take them out a few days before you want to eat them to let them ripen. 

You can also totally let them ripen on the vine. They will be sweeter this way. You will also potentially have a lot of berries to eat all at once, since they don’t last long after ripening on the vine. This is where you can turn some into jams and pies.

Hardy Kiwi in a Permaculture Setting

Hardy kiwis are a great addition to a permaculture garden, homestead, or food forest. Common companion plants or guild mates include: white clover, strawberries, lovage, lemon balm, bulb flowers like daffodils, comfrey, and others. 

Tip: If your soil is not acidic enough for hardy kiwi, (which prefers soil ph 5.5 to 7) consider mulching with pine needles to let the soil become more acidic. 

Hardy kiwis are still typically grown on a trellis, rather than a tree, despite growing on trees in the wild. This is mainly to make them easier to harvest. A male plant, however, doesn’t need to be harvested, so you could consider letting it naturally vine up a tree. Be careful about growing it by a fruit tree such as an apple or pear tree, because they might overwhelm it. 

Common Cultivars: What Species Should You Try and Grow?

There are a few different varieties of Hardy Kiwi. Some can take more cold, and others can take more heat. They have different fruiting times and amounts, and prefer slightly different soil conditions. One variety even can self-pollinate! I found an excellent article describing different cultivars, and I recommend you check it out. I’ve quoted the most important information, though, here:

Actinidia arguta — Zones 5 through 10. Mature plants produce up to 100 pounds of fruit per season. Pest- and disease-free.

‘Anna’ — Zones 5 through 10. In Russia, this variety is called ‘Ananasnaya’, meaning “pineapple-like.” It is vigorous, productive, and promising commercially. Very ornamental with red leaf stems. One of the best-tasting (“addictive”) and sweetest of the hardy kiwis.

‘Dumbarton Oaks’ — Zones 5 through 8. Excellent flavor and early ripening.

‘Issai’ — Zones 6 through 10. Only self-fertile variety (a male pollenizing plant is not needed). Fruits the first year after planting. Medium-sized green fruit. Susceptible to spider mites in hot, dry climates.

A. cordifolia — Zones 5 through 10. Perhaps the sweetest of all and the first to ripen. It has been less successful in the Pacific Northwest.

A. kolomikta ‘Arctic Beauty’ — Zones 3 through 8. Best suited to short-season and cold-winter areas. Compared to A. arguta, plants are smaller and more delicate; fruits are smaller and ripen earlier. Fruits first year after planting. Plant where it receives partial to full shade. Leaves of male plants start the season deep green, then paint themselves with splashes of white and pink.

A. purpurea ‘Hardy Red’ — Zones 5 through 10. Vigorous vine; oblong red fruit is sweet with a bit of tartness.”