Kiwi are deciduous vines that make a great addition to your landscape. They offer elegant vining branches with delicious fruit. Explore our Kiwi Growing Guide for all of tips on how to be successful with kiwis.
Jump to: Kiwi Varieties, Pollination, Site Selection, Watering & Fertilizing, Pruning & Training, Spring Forst Protection, Winter Care for Fuzzy Kiwis
KIWI VARIETIES
There are four types of Kiwis we can grow for fruit in the US. Each of these varieties produce fruit and are suitable to different climates.
Fuzzy Kiwi (Actinidia deliciosa)
Native to central-southern China and has long been cultivated to give us the delicious fruit we have today, commonly found in grocery stores. Produces fruit with brown fuzzy skin and bright green flesh. A very vigorous vine that is hardy to about 0°F (USDA Zone 5) and grows to about 8-10 feet in width on a support structure.
Hardy Kiwi (Actinidia arguta)
Native to Japan, Korea, Northern China, and Russian Far East. Often known as the kiwiberry, produces smaller, very sweet and flavorful fruit that has a smooth skin and can be eaten just like grapes. It is a very vigorous shade-tolerant vine and, depending on the variety, is hardy to -25°F (USDA Zone 4). It grows to about 10-12 feet in width on a support structure.
Arctic Beauty Kiwi (Actinidia kolomikta)
Native to Japan, Korea, Eastern China, and the Russian Far East. It is a more compact vine that also produces smaller, but very flavorful fruit with smooth skin. The leaves of the Arctic Beauty Kiwis are variegated with white and pink coloring. These are shade-tolerant and cold hardy down to -40°F (USDA Zone 3). It grows to about 6-12 feet in width on a support structure.
Silver Vine Kiwi (Actinidia polygama)
From the mountains of Korea and produces small fruit with smooth skin. Its fruit is more elongated than the hardy kiwi but is similar in size. The leaves are variegated with while coloring as well. These are shade-tolerant and cold hardy down to -40°F (USDA Zone 3). It grows to about 8-10 feet in width on a support structure. Silver Vine is also used a stimulant for cats, often as a substitute for cat nip!
POLLINATION
All kiwi varieties require both a male and female plant for cross pollination. One male plant can pollinate up to 8 females as long as they are within about 40 feet of one another. All male varieties will be labeled with “male kiwi” in the product title. All other varieties not labeled as male are female kiwis. Kiwis are pollinated by both insects and wind pollination. It can be helpful to know which direction your spring winds come from to ensure your male plants are upwind from the females.
SITE SELECTION
All Kiwis like well-drained soil, from clayey to sandy. Fuzzy and Hardy Kiwi like 1/2 day to full sun. Arctic Beauty Kiwi and Silver Vine like more shade and are happy on a partially shaded arbor or the northside of a fence or wall. If your soil is very wet, you can make a mound of soil several inches above the soil surface and plant with that as your soil line. This will encourage the water to drain away from the roots.
Support Structures
All kiwis are twining vines. Because of their vigor and heavy crops, Fuzzy and Hardy Kiwi need a strong arbor, trellis or other support. A typical arbor for these species would be 12 feet long, 6 feet wide and 6 feet tall. Use 4×6 or larger, pressure treated posts and 4×4, 2×6 or larger cross arms for your arbor. Hi-tensile, New Zealand style fence wire works well when spaced 1 1/2 to 2 feet apart across the cross arms. Arctic Beauty and Silver Vine kiwis are less vigorous and bear less fruit so they can be grown on a fence, wall, garden trellis, or other such support.
Spacing
When planting along a fence, wall, or trellis, the Fuzzy and Hardy varieties should be at least 15-18 feet apart. Arctic Beauty and Silver Vine can be planted 10-15 feet apart as they are less vigorous.
WATERING & FERTILIZING
All kiwis have a shallow, spreading root system and need adequate water during the growing season. A 4-6 in. deep mulch in a 2-3 ft. circle around the plants will conserve moisture and deter weeds. Hay, straw or compost are good materials for mulching. During warm weather, a deep watering once a week should be sufficient. Be sure to check the soil and be careful not to overwater your plants. Reduce watering frequency in early fall to harden off your plant for winter weather.
Because of their vigor and rapid growth rate, Fuzzy and Hardy Kiwis can use abundant amounts of nitrogen. After the first year, applying 1/2 lb. per plant of nitrogen annually in early spring will ensure good growth throughout the summer. We recommend using organic sources of nitrogen. For example, if an organic fertilizer contains 5% nitrogen, apply 10 lbs. per plant. After 4-5 years, increase the nitrogen to 1 lb. annually. Arctic Beauty Kiwis also benefit from annual fertilizer applications, but because of their lower vigor, they should need no more than 1/2 as much as the Fuzzy and Hardy Kiwis.
PRUNING & TRAINING
Establishing a Structure
After planting, tie your plant loosely to its support. Once roots are established and growth begins, your Kiwi will likely produce one or more vigorous shoots from near the base of the plant. After these shoots grow approximately 2 feet, tie the strongest to a stake and allow it to grow to the top of your trellis. Tip back the other shoots at this time so they won’t compete with one you have chosen.
After the main shoot reaches the top of your trellis or support, you can remove the other less vigorous shoots, leaving the one you have chosen to become the main structural trunk of your Kiwi vine. After the main shoot grows past the top of your trellis, cut back the tip and allow two upper buds to grow. Train these new shoots to grow laterally along the wires or structure of your arbor or trellis and tie them loosely. These new shoots will form the lateral cordons and become the permanent structure of your Kiwi.
By the end of the second season, you should have a good framework established for your Kiwis. During the second winter, prune back the new cordons (side shoots) to 10-12 buds. The lateral shoots from these basal buds will produce shoots, which can bear your first flowers and fruit. Train one of these shoots along the trellis or arbor to add length to the cordon and repeat the pruning process the following winter. Continue this process until the cordons reach the limit of your support.
Annual Maintenance
Kiwis flower and bear fruit on shoots that have grown from the previous season’s growth. Annual pruning during the dormant season is important for good fruit production. Pruning is best carried out in December or January and consists of heading back the previous year’s new shoots to 10-12 buds and removing older wood, if any, that has already fruited. In addition, twisted, tangled and broken shoots should be removed as well as those crossing from one side of the plant to the other. Any shoots hanging to the ground should be removed or tied to the support. As you prune and observe your Kiwis, you will get a sense of what should stay and what should be removed.
Male plants are grown and pruned in the same way as female plants, but, since they are grown only for their flowers they need only about 1/4 of the trellis space and can be pruned more severely.
*Please note that it may take 3-4 years or more before Fuzzy and Hardy Kiwis begin flowering and fruiting.
SPRING FROST PROTECTION
Depending on the species, Kiwis can withstand temperatures from 0°F to minus 40°F. While the plants are hardy to these temperatures, the new shoots and flowers of all Kiwis can be damaged by temperatures below approx. 31°F. If plants have begun growth and frost threatens, a simple way to prevent damage is to sprinkle your plants during the night with water. While ice will form on the plant, the temperature of foliage will not fall below 32°F. If the plant is small, you can simply cover it with plastic or fabric.
WINTER CARE FOR FUZZY KIWIS
While the Fuzzy kiwi is hardy to 0°F, the temperature difference caused by a sunny weather and cold nighttime temperatures that fall below 20°F can cause issues. The warming of the plant from the sun causes sap to flow which can then freeze at night and damage the trunk. In severe cases, this may result in girdling of the trunk and death at the top of the plant. While shoots may come from the base and they plant can recover, the top growth of the plant is lost.
The best way to prevent this damage is to wrap the lower 2 to 3 ft. of the trunk with some kind of insulating or reflective material. Painting the trunk with a 50/50 mix of water and white, interior latex paint can also help prevent this damage. In addition, mulching the base of the plant with straw or other material will also help protect your Fuzzy Kiwi during severe winter weather.
Can’t decide which kiwi to get started with? Need help to be successful growing this vine?Contact us via email at info@onegreenworld.com or leave us a voicemail at (877) 353-4028