Are you looking for something new to grow? If you have a good place for it, hardy kiwi is an interesting plant to try. Hardy kiwi (Actinidia arguta) is a cousin of the brown, fuzzy kiwi available commercially (A. chinensis). The hardy kiwi can tolerate temperatures below 0°F and is growing in popularity in the northern United States. The fruits are smaller than A. chinensis and have smooth skin and small seeds. They can be eaten whole without being peeled, dried or even made into wine. The flavor is similar to the fuzzy kiwi and very good!
The hardy kiwi plant is a woody perennial vine and requires pruning and training similar to grapevines. It can grow to a length of 40 feet if left unpruned. This is a dioecious plant, meaning that male and female flowers are produced on separate plants. For pollination and fruit development, it is necessary to have both male and female plants. It is recommended to have at least one male for every six females.
Kiwi can be grown in a variety of soil types as long as the pH is 5.5-7.0 and the soil is not poorly drained. The roots are sensitive to fertilizer burn so use fertilizer cautiously. No fertilizer is needed in the first year. In subsequent years, increase application rate from 2 oz. 10-10-10 per plant in the second year increasing by 2 oz. per year up to 8 oz. per plant.
Hardy kiwi produces fruit on shoots from canes grown the previous year. Pruning is done during the dormant season and during the growing season. As with grapes, up to 70% of the wood is removed during dormant pruning, leaving some of last year’s growth for fruiting. The vines can be trained to a trellis or a variety of forms. The illustration shows pruning for the first two seasons. Most vines will not produce fruit until they are 5-9 years old.
First two years of training a kiwi vine. (below left)
(Courtesy of Oregon State University) (A) Prune to two buds at planting.
(B) Train one shoot as trunk, remove all others (growing season, year 1).
(C) Head back trunk as shoot growth at terminal loses vigor (growing season, year 1).
(D) Continue to remove lateral shoots, let trunk grow beyond wire, then head to just below top wire (growing season, year 1).
(E) Choose two shots to form cordons (lateral trunks). Head back to 1/4 inch diameter in dormant season (growing season, year 1).
(F) Shoot growth, year 2. Pruning cuts in dormant season of year 2 also are shown by //.
Although the hardy kiwi is quite winter hardy, new shoot growth and flowers are easily injured by frost. Some years, frost damage kills the flowers and no fruit develops.
A mature hardy kiwi plant will produce 50-100 pounds of fruit. The fruits can be allowed to ripen on the vine or they can be harvested early and will ripen in storage. Harvesting early will extend the storage life to about 2 months. More information on growing hardy kiwi is available at http://www.hort.cornell.edu/forestfarming/content/crop-fact-sheets/hardy-kiwi.pdf