Kiwis are attractive and tasty eaten by themselves or in fruit salads.
When they hear the name "kiwi" most people think of New Zealand, the flightless bird, or the fruit. They're all connected. Although kiwi fruit is associated with New Zealanders, the vine is native to Southeast Asia. New Zealand started growing and exporting the fruit commercially in the 1950s. Originally called the Chinese gooseberry, the fruit was renamed after New Zealand's national bird. Today, kiwis are grown commercially around the world, including Australia, China, Italy, Chile, and the United States.
You don't have to travel far to enjoy these exotic fruits. Kiwis are one of the most versatile fruits you can grow in your backyard. There is a type for almost every climate in our country and the vigorous vines make a beautiful landscape feature when trained on a pergola, trellis, or fence. Plus, kiwis are good for you. The fruit boasts more vitamin C than oranges, more potassium than bananas, and contains folate, copper, fiber, vitamin E, and lutein.
Kiwis have a tart taste, but I like it! While most people peel fuzzy kiwis, I eat them skin and all.
There are two categories of kiwis: fuzzy and hardy. The familiar fuzzy kiwi (Actinidia deliciosa), with brown skin and green flesh, has a tart flavor. The recently introduced golden kiwi (A. chinensis) has a sweeter flavor and yellow flesh. The vines of fuzzy kiwis are hardy to USDA zones 7 and 8, so they're best grown on the West coast and in the South.
The hardy kiwi produces a smaller fruit than the fuzzy kiwi. The skin is smooth and green, the flesh is sweet, and the vines are prolific producers. There are several species. Actinidia arguta can be grown in USDA zones 5 and 6. A. kolomikta is probably the most hardy, adapatable to regions as cold as zone 3. A. purpurea fruits have red skin and flesh and the plant is hardy to zone 6. Hardy kiwi is less likely to be found in markets because the grape-like fruits don't ship well.
Kiwi vines are dioecious, which means there are separate male and female plants. In order to get fruit you need both a male and female plant. (For optimum production on a larger scale, plant one male for every six female plants.) All kiwis produce the most fruit in full sun, but the hardy kiwis will tolerate part shade and still produce some fruit. Choose a slightly sloping site with good water and air drainage that's protected from winter winds. Heavy, wet clay soils tend to initiate root rot on kiwi.
Here are some kiwi varieties to grow in your yard this summer.
Kiwis grow in clusters on vines that need strong support and heavy annual pruning.
Kiwi vines bloom early and tender flowers can be damaged by spring frosts. Choose a planting site that is sheltered from cold winter winds and, if possible, plant on a slope so cold air will flow down and away from vines.
Set vines in spring. Loosen soil and amend with compost before planting. If soil is poor, mix in a slow-release organic fertilizer to get young plants off to a strong start. Space female kiwi vines 15 feet apart. (Some hardy kiwi varieties, such as 'Arctic Beauty', can be spaced as close as 8 feet apart.) Plant male vines within 50 feet of the females for optimum pollination. Since the male vines don't produce fruit, they can be used as ornamentals without the concern of fruit littering the ground. Keep plants well watered, especially during their first growing season.
Once established, fertilize in spring before growth begins and again in early summer after flowering. Kiwi roots are very sensitive to fertilizer burn, so use choose slow-release or organic products.
Fuzzy kiwis are the most popular type of this fruit and commonly found in markets.
Trellis your kiwi vines on a fence, pergola, or wire trellis similar to grapes. Kiwi plants grow large and can live up to 50 years, so make the structure sturdy and long-lasting. For a simple trellis, drive in a 4- to 6-inch-diameter post on either end of the kiwi row and attach a 5-foot-long, 2- by 4-inch wooden cross piece on the top of each post perpendicular to the row to form a T . Stretch and attach 3 heavy gauge wires down the row, one down the middle and one on each end of the cross piece.
Kiwi vines are vigorous growers and need heavy pruning to fruit to their full potential. Here's one method of pruning that is similar to grape pruning. Prune young vines to have one leader tied to the wire trellis. In subsequent years, prune female vines each year in mid-winter, removing all dead, diseased, and broken branches and any branches that fruited the previous summer. Don't wait until late winter or early spring to prune; kiwi branches tend to bleed sap if cut too late. Leave the one-year-old wood that hasn't fruited yet; that's where the new fruit will form. Cut these arms, or laterals, back to 8 to 12 buds. Prune male vines in summer after the pollen-rich flowers have finished blooming.
Young kiwi trunks are very susceptible to winter injury. In fall protect the trunks with a tree wrap.
Kiwis take 1 to 3 years to begin producing fruit, depending on the variety. The attractive flowers form in late spring; fruit sets in midsummer and ripens in fall on most types. Starting in September, harvest a few kiwis and let them ripen indoors on a windowsill or in a paper bag. When the kiwis are soft, taste one; if the flavor is sweet, pick the remaining fruit. If the kiwis begin to soften on the vine, pick them all and refrigerate or they will rot. Harvest all fruit before the first frost. Kiwis will last for five to six weeks in the refrigerator.
Photos courtesy of the California Kiwi Fruit Commission