The kiwi plant, or Chinese gooseberry, is well known as being a warm weather plant. It has grown wild in the warm climates of Asia for many centuries.
Its love of warm climates means that many gardeners have assumed that they will never be able to grow their own kiwi plant. However, new, hardy kiwi plant varieties (Actinidia arguta) are more tolerant to cooler climates. While not identical in appearance to the typical fuzzy kiwi fruit, these hardy cultivars still have the distinctive kiwi taste.
Traditionally a warm weather fruit, hardy cultivars mean that anyone can successfully grow Chinese gooseberry.
The hardy kiwi plant is native to Russia and China. This means that it can survive in cooler climates than the more traditional cultivars.
Hardy kiwi fruit is smaller than the varieties you find in grocery stores. The fruit of the hardy cultivar is usually the size of a large grape and has a rosy hue. An aromatic fruit, their skin is tender and edible. Like other less hardy varieties, they are packed with Vitamin C.
If you want to grow your own hardy kiwi plant, this guide will take you through everything that you need to know.
Different Kiwi Plant Varieties
There are a range of different hardy kiwi plant varieties available. While garden stores may sell some specimens, specialist nurseries often provide you with access to a wider range of cultivars.
When selecting your kiwi plant, bear in the mind preferences and eventual size of the cultivar. Try to select a kiwi plant that is best suited to your growing situation.
You will also need to purchase both male and female varieties. This is vital for pollination and fruit production. As a general rule, one male vine can pollinate up to 8 females.
If you are unsure whether your Chinese gooseberries are male or female, look at the flowers. Male flowers hold pollen, meaning that their center is yellow. Female flowers don’t hold pollen so they are more uniformly white.
If you are growing for fruit you will need both male and female cultivars. If space is at a premium you can also grow a self fertile variety.
Russian cultivars are particularly hardy and cold tolerant. Natasha and Tatyana are two reliable cultivars. They can be pollinated by the equally resilient Andrey (A. arguta) cultivar.
Hayward (Actinidia deliciosa) is a widely grown female kiwi plant. A late flowering cultivar, it produces large, oval fruit with a good flavor. Tormuri (A. deliciosa) is a male late flowering cultivar that is suitable for pollinating the Hayward cultivar.
If space is at a premium, choose a self fertile variety. Jenny is a reliable self fertile cultivar which is pleasingly resilient. Jenny is prized for its flavorsome fruit.
Other popular female cultivars include Michigan State which generally produces larger fruit than other cultivars and Ken’s Red. This cultivar is known for its plum red, sweet fruit.
How to Grow Hardy Kiwis
Growing a Chinese gooseberry is a commitment. These vines take several years to mature, and many don’t bear fruit until they are at least 5 years old. Some varieties can take up to 9 years before they start bearing fruiting. Growing from seed can take even longer.
The key to successfully growing kiwis is planning. The kiwi plant needs lots of space. Each vine can reach over 20 ft in height. This means that you will need to space each your vines 10 to 18 ft apart.
The hardy kiwi plant also has a vigorous growth habit. To support this you will need to provide sturdy support such as a secure trellis. This support should be both horizontal and vertical. Remember to support the trunk as well as the vines.
Growing from Seed
Purchasing young specimens is often the easiest way to get started. However you can also grow from seed. But be warned, this is a lengthy process.
Acquiring seeds from a nursery means that you know exactly whether you are growing male or female vines. However, you can also try growing seeds harvested from fruit. While this is possible, seed from store bought fruit may not be from hardy varieties meaning that it will struggle in your climate.
To harvest the seeds simply scoop them out of the fruit and gently rinse under water, washing the pulp away. Allow the seeds to dry out for a few days before beginning the next step.
Seeds require a period of chilling before they will germinate. To do this, half fill a resealable bag with moist perlite. Gently push the seeds into the perlite and seal the bag. Place it in the refrigerator at about 40 ℉ for about 4 months. Regularly check the bag and mist the perlite to prevent it from drying out.
After the seeds have chilled sow in trays filled with moist potting mix. Gently sprinkle the seeds over the surface before covering lightly.
Keep the soil moist. A gentle spray, such as one from a Plastic Spray Bottle, should be enough to moisten the soil without disturbing the seeds. The tray should be covered or placed in a propagator during this time to maintain an even humidity level. A propagator such as the Super Sprouter which comes with its own heat mat enables you to maintain an even temperature around your seeds. This helps to speed up the germination process.
In warm conditions germination takes about 4 weeks.
Following germination place the trays on a sunny windowsill.
When the seedlings are large enough to handle thin them out so that only the healthiest remain. Once the last frost date has passed the seedlings can be hardened off and planted outside.
Selecting the Ideal Position
The chosen position should be light but sheltered. Planting against a west or south facing wall is ideal. In warmer USDA Zones you can plant in an open area. In colder areas you may have more success growing the vines in a greenhouse.
If space is limited, try a self-fertile cultivar. This significantly reduces the number of vines that you need.
You can grow a kiwi plant in the soil, in a raised bed, or in a pot. This is recommended if you have poorly draining soil. A 15 to 45 gallon pot or grow bag is ideal. If you do plant in a pot, make sure that it is clean and has lots of drainage holes in the bottom.
The kiwi plant does best in well-draining soil. Loamy soil is ideal. Use a soil test kit to gauge the quality of your soil. It should have a pH level of between 5 and 7. If your soil is particularly alkaline there are a number of ways to make it more acidic.
How to Plant
Wait until the last frost has passed before you harden off your specimens. Transplant seedlings and rooted cuttings in the spring, once the soil is workable.
Before planting work in lots of organic matter to enrich the soil. You can also work blood, fish and bone fertilizer into the soil.
Dig a hole in the soil large enough to hold the root system. When placed in the hole the kiwi plant should sit at roughly the same level as when it was in the container.
Position the Chinese gooseberry in the center of the hole and gently backfill. Firm down the soil and water well. Mulch around the base of the stem.
If your soil is lacking in nutrients or doesn’t drain well, try growing in raised beds.
The kiwi plant dislikes sitting in wet soil. If you are growing in heavy soil, or soil that has poor drainage, instead of digging down, mound the soil up. Position your kiwi plant in the center of the mound so that its roots are always above soil, and water, level.
Wherever you choose to grow, you will need to protect young vines from frosts. Once established the hardy kiwi plant can tolerate temperatures as low as 32 ℉.
Remember to space your Chinese gooseberries out to the recommended distance, usually at least 8 ft. Be careful not to overly distance the vines. Planting the vines in close proximity to each other helps to encourage pollination.
How to Care for a Kiwi Plant
Once established these vines require regular attention to support their vigorous growth habit.
When to Water
Water regularly. Aim to keep the soil moist. This is especially vital during the growing season. During hot periods you may need to water as frequently as 3 times a week.
Be careful not to overwater the vines. Water only when the soil is noticeably starting to dry out.
Plants growing in pots or in greenhouses also require more frequent watering than those in the ground. If you are unsure when to water, a soil moisture meter is a useful gadget. The Surenshy Soil pH Meter not only monitors the moisture content of your soil, it also reads the pH level. This is particularly useful when working out which fertilizer to apply.
Fertilizing your Vines
Don’t fertilise straight away. Allow the vines time to settle.
Fertilize in the first spring following planting. You should always wait until new growth has emerged before you fertilize.
A general purpose fertilizer is ideal. You can also apply a formulated citrus and avocado fertilizer. A soil test will tell you if your soil is lacking in nutrients. This information can guide which type of fertilizer you need to apply.
Each fertilizer will have its own recommendations in regards to how much you should apply. Always consult the packet before fertilizing. In general, if using a general purpose balanced 10-10-10 fertilizer, apply two ounces of fertilizer per plant. Increase this by 2 ounces every year until you reach 8 ounces. The applied dosage should never exceed 8 ounces.
When fertilizing, make sure that the soil is moist. Water the day before. While water soluble or liquid fertilizers are easier to apply, granular fertilizers can also be used. Make sure to water the fertilizer in well. This prevents the roots from becoming burnt.
Regularly watering and fertilizing your vines keeps them healthy and encourages lots of fruit to grow.
Apply a Layer of Mulch
Applying a layer of organic mulch around the base of the stem helps the soil to conserve moisture.
Mulch in late winter with well-rotted manure. This gives the vines a nutritional boost as well as providing the roots with some protection from cold temperatures.
Don’t allow the mulch to touch the stem, this can cause it to rot.
Even though the kiwi plant can withstand temperatures down to 32 ℉ it can still require some protection. Cover the trunks of vines growing outdoors with a horticultural fleece or blanket, such as the Kupton Plant Cover.
This protection is particularly important in the first spring after planting while the stems are still young and vulnerable. Older vines are more resilient.
Unless you are growing self fertile varieties, you will need to cultivate at least two kiwi vines in order to grow fruit. Depending on your growing space, this may not leave room for many companion plants.
If you do have some free space, try planting other fruits such as currants, grapes, raspberries, grapefruit and blueberry. They all work well together and share similar growing needs.
Always use sharp garden scissors or pruners. This enables you to make clean, precise cuts. Sterilizing your tools before and after use helps to prevent disease and infestations from spreading between your crops.
The kiwi plant has a vigorous growth habit. This means that you need to prune your Chinese gooseberries once in the winter and again two or three times during the summer.
Pruning during the winter is particularly important. The pruning of dormant specimens is often more severe than summer pruning, which largely consists of tidying up. Regular pruning is a key part of maintaining a healthy and productive garden.
During the winter, concentrate on pruning branches that bore fruit the previous year. Also remove any dead or crossed branches.
Allow as many one year old branches to remain in place as possible. These are the branches that produce the most fruit. If they do require pruning, trim them down to about the 8th node from the base. The nodes are important because they push out new fruiting spurs during the summer.
In the summer prune away long, arching vines that extend beyond the developing fruit. Prune this terminal growth back to roughly 4 to 6 leaves beyond the last flower. Vines that aren’t flowering but reach beyond the trellis can also be pruned away. You can also prune away old wood and entangled stems and shoots.
During the first year after planting, regularly prune and train the vines to encourage a straight and upward growth habit.
Common Pests and Problems
Blight and rot can be particularly troublesome, as can root knot nematodes. The easiest way to keep the kiwi plant free from problems is to provide proper care. Establish a regular water routine that suits your crop. This helps to prevent overwatering and the many issues soggy roots can cause.
Regularly check the stems and foliage for signs of infestation. Spiders mites, thrips, Japanese beetles and leafrollers can also target Chinese gooseberries. Should infestation strike, use insecticidal soap to remove the pests. You can also try encouraging beneficial insects such as lacewings to your garden. This can be done by planting insect friendly flowers or building a bug hotel.
A bug hotel is a great way to attract beneficial insects to your garden. As well as encouraging pollination this helps to keep your garden healthy.
Pollinating a Kiwi Plant
While these are attractive ornamental vines, the main reason for growing a kiwi plant is the fruit.
Often visiting pollinators will do the job of pollination for you. However you may want to give your flowers some help and hand pollinate yourself. This may also be necessary if you are growing the kiwi plant undercover.
The male kiwi plant produces staminate flowers. These are usually yellow in color. The female kiwi plant produces pistillate flowers. These bear the fruit and are white or paler than the male flowers.
Kiwi flowers may require some help from you in order to become pollinated.
Only try to pollinate flowers that open at roughly the same time. Male flower blossom is only viable for a few days after the flowers first open. Female flowers can be pollinated for at least a week after opening.
The simplest way to pollinate your female vines is to take some male flowers and brush them over the open female flowers. You can also use a device such as the JKSH Pollination Machine to pollinate your flowers.
Harvest and Storage
If your attempts at pollination have been successful, the flowers will soon develop fruit. Continue to care and water for the vines during this period. Allow the fruit to remain on the stem for as long as possible. This gives it lots of time to ripen.
Pick the fruit before the first frost hits. If you do pick unripe fruit, place it on a sunny windowsill to ripen. You can store large numbers of unripe fruit in the refrigerator. They can then be brought out in small numbers and placed on the windowsill to ripen. The fruit can keep in the refrigerator, in pierced plastic bags, for up to 3 months.
Allow the fruit to remain on the vine for as long as possible before harvesting.
The hardy kiwi is a surprisingly resilient variant of the warm weather loving plant. With a little special care and attention these vines can be encouraged to grow and fruit in a range of conditions, allowing you to enjoy great tasting, fresh kiwi fruit.