PNW 507 • Reprinted September 2000 $2.50 Growing Kiwifruit Contents Bernadine Strik, Extension berry Kiwifruit Cultivars crops specialist, and Helen Cahn, research assistant, Oregon State “Fuzzy” Kiwifruit ....................................................................... 2 University. Hardy Kiwi ................................................................................. 3 This publication replaces Oregon Kolomikta Kiwi .......................................................................... 4 publication EC 1464, Growing Silver Vine Kiwi ......................................................................... 5 Kiwifruit. Establishing Your Kiwifruit Vineyard Site Selection and Preparation .................................................... 6 Vineyard Planning, Planting, and Spacing ................................. 7 Irrigation ..................................................................................... 8 Fertilization............................................................................... 10 Trellis ........................................................................................ 11 Training Young Vines ............................................................... 12 Maintaining Your Kiwifruit Vineyard Fertilization............................................................................... 15 Irrigation ................................................................................... 16 Pollination................................................................................. 16 Fruit Thinning ........................................................................... 16 Pruning and Training ................................................................ 17 Harvest, Handling, and Storage of Kiwifruit Fruit Maturation........................................................................ 19 Harvesting................................................................................. 20 Storage ...................................................................................... 20 2 Kiwifruit Cultivars B. Strik and H. Cahn iwifruit are Although some people claim native to they eat the skin of fuzzy kiwi, southeast Asia. most peel these fruit. However, There are more the hardy, kolomikta, and silver than 50 species in vine kiwifruit have very edible Kthe genus Actinidia, and many skin. You can pop these delicious, have commercial potential. small fruit right into your mouth. The most common kiwifruit Kiwifruit are relatively high in species grown commercially is acid, reaching nearly 2 percent of Actinidia deliciosa cultivar fresh weight at maturity and Hayward. Consumers are very declining after harvest. Kiwifruit familiar with this brown, fuzzy are one of the best natural sources fruit. of vitamin C, with a level of at Fuzzy kiwi are grown commer- least twice that of the orange. cially in New Zealand, Italy, The fruit of most common Japan, France, Australia, Greece, kiwifruit species and cultivars Chile, and California. There is have green flesh that does not some commercial production in brown when cut. Oregon and Washington; however, Fuzzy kiwifruit can be stored this species is not extremely hardy for months after harvest. However, and may suffer cold injury in the hardy and kolomikta kiwis can some years in the Pacific North- be stored for only 2 months at west. most at 32–35.5°F (0–2°C). More hardy kiwifruit species The kiwifruit is a dioecious also are available. They include plant—it has separate male and the following: female plants (with the exception • A. arguta, known as the hardy of a few self-fertile cultivars). It is kiwi or arguta (marketed as essential to plant male vines for baby kiwi in Oregon and grape pollination and crop production. kiwi in British Columbia). This Plant male and female vines of species shows promise for the same species. In general, commercial production in the 1 male is required for every 6 to United States. 10 females. Self-fertile cultivars require no male pollinator, al- • A. kolomikta, also though fruit size may be larger known as kolomikta with cross-pollination. or Arctic Beauty Yield per plant varies with • A. polygama, or species and cultivar. Hayward silver vine (A. deliciosa) yields from 25 to 1 200 pounds per plant, whereas Fuzzy kiwifruit can be grown in Hayward A. arguta yields from 50 to Oregon and Washington. Hayward Hayward is the cultivar usually 100 pounds per plant. needs a growing season of about found in stores. Its large, fuzzy, A. kolomikta and A. polygama 225 to 240 frost-free days. How- brown fruit with good, sweet leaves contain a substance that has ever, although this species should flavor has made it popular. Shoots an effect similar to catnip. In tolerate temperatures down to are sensitive to frost injury in China, kiwivine leaves reportedly 10°F (-12°C), plants may be spring. This cultivar is recom- are fed to large cats as a sedative. damaged at slightly higher tem- mended only for areas of Oregon You may find that cats become a peratures. and Washington with mild pest of your new kiwifruit plant- Cold damage usually occurs winters. ing! when temperatures drop during Ripening date: October 7–12 The information below on the night after a warm spell. The Fruit weight: 80–90 grams ripening dates, fruit weights, and trunk usually is damaged, which Vine growth: vigorous plant performance is approximate. weakens older plants and some- It is based on limited test results times kills young vines. Although Bruno from a cultivar planting at North methods such as wraps and plastic Bruno produces a large cylin- Willamette Research and Exten- sleeves may help protect the trunk drical fruit that is darker brown sion Center (NWREC), Aurora, against freeze injury, they are not than Hayward. It has a lower Oregon. Performance may vary always effective. The trunk’s winter chilling requirement with location. sensitivity to cold decreases with (50–250 hours at 32 to 45°F), and age. therefore may be more sensitive to “Fuzzy” Kiwifruit Young kiwifruit shoots and fruit late winter cold spells, particularly are very sensitive to frost injury. after a warm period. Actinidia deliciosa, fuzzy Temperatures of 30°F or less kiwifruit, is the most widely (-1°C) for only 30 minutes can Saanichton 12 available species. Generally, fruit severely damage shoots in the This cultivar comes from are large, with a green skin spring and fruit in the fall. Still, Vancouver Island, British Colum- covered with brown fuzz. Vitamin these kiwifruit can be grown bia, where it has been grown for C content ranges from 100 to successfully with overhead more than 30 years. Fruit are 200 mg per 100 grams fruit. The irrigation for frost protection. large, somewhat more rectangular most common commercial culti- Although many other fuzzy than Hayward, sweet, and of good var is Hayward, which is found in kiwifruit cultivars are available in flavor. It seems more hardy than supermarkets throughout the other production Hayward. world. However, other varieties regions, the follow- Ripening date: October 1 also are available. ing cultivars are Fruit weight: 70–80 grams available and have Vine growth: vigorous been tested in the Blake Pacific Northwest. This is a relatively new cultivar. All produce bright It is claimed to be “self-fertile,” green-fleshed fruit. but it does benefit from cross- Ripening dates pollination. Fruit are smaller than given below are based Hayward or Saanichton 12 and are on when fruit reached ° more oval in shape. Flavor is 6.5 Brix (percent sugar) at inferior to Hayward and NWREC, a harvest date Saanichton 12. criterion for long-term storage Ripening date: October 1 (see “Harvest, Handling, and Fruit weight: 60–70 grams Storage of Kiwifruit”). Vine growth: vigorous 2 Kiwifruit Cultivars Male (A. deliciosa) A. deliciosa. Fruit are smooth Ananasnaya A pollinator is required for all skinned (skin can be eaten), This is the most popular hardy fuzzy kiwi. There are many generally green in color, and much kiwifruit cultivar currently avail- cultivars/selections of males smaller than the fuzzy types. The able. Its Russian name means available. Examples include flavor is excellent, but varies by “pineapple-like.” You also may Matua, Tomuri, Cal Chico No. 3, cultivar. Vitamin C content is hear this cultivar referred to as Chico Early, and Chico Extra very good at 10 to 70 mg per “Anna.” Early. 100 grams fresh fruit. Fruit are of very good quality, In France, hardy kiwi are with a good aroma and sweet, Hardy Kiwi cultivated commercially, but intense flavor. They have a green acreage is limited due to market- skin that develops a purple-red This kiwifruit species, ing limitations—small fruit size, blush in full sun. Skin may be ° A. arguta, is hardy to -10 to -25 F short shelf life, and a limited slightly tough. ° (-23 to -32 C) under most condi- ripening period. Also, the fruit on The cultivar Ananasnaya tions. Damage to the trunk from a given plant ripen unevenly, brought to Oregon is A. arguta. cold temperatures rarely occurs in which makes harvest difficult However, the Russian cultivar Oregon or Washington; however, unless fruit are picked under-ripe Ananasnaya is A. kolomikta; frost damage to young shoots is and forced to ripen. Vines are very more than one cultivar with the more common. vigorous, and considerable same name may be available in Maximum hardiness levels pruning is required to keep growth nurseries. given for this species reflect only under control. Harvest date: September 14–30 midwinter hardiness. This species In general,