By Bob Purvis
Nanking cherry (Prunus tomentosa) has been grown as a substitute for pie cherry trees by Alaskan gardeners for many years because of its hardiness (zone 2—it has fruited in Fairbanks, as well as in Anchorage). Unfortunately, I know more than a few Alaskans who have had great difficulty getting their bushes of Nanking cherry to bear fruit.
Erik Simpson reports that an acquaintance of his tried the following technique when faced with the problem. He removed the last one-third (1/3) of the season’s growth from his unfruitful Nanking cherry bushes in early- to mid-August. The following year, the bushes blossomed profusely and set a good crop of fruit Summer pruning, which this was, often has as one of its effects the channeling of nutrients away from branch tips (since they have, of course, been removed) and into the buds that remain, with the consequence that they oftentimes are more likely to develop into flower buds. It also tends to reduce somewhat the vigor of the bush or tree.
Other possible causes of unfruitfulness would include growing the bushes in poorly drained soil or in an overly shady location. Failure to provide adequate fertilizer, as evidenced by skimpy terminal growth or yellowing leaves, is another possible cause. A third is related to the fact that Nanking cherries are not self-fruitful. At least two (2) bushes are needed to cross- pollinate one another, but to be safe it would be wise to plant as many as five (5). They should be pruned to allow adequate penetration of sunlight into the interior, and spaced far enough apart-five (5) feet-to allow them to spread.
Speaking of memberships, welcome to Rudy Domke, a new member from Fairbanks. Rudy’s main interest is strawberries. He has been working since 1961 on locating hardy parent plants to cross and develop a better strawberry for the Interior. We also have a new honorary member in our group—Roger Vick, of the University of Alberta, Devonian Botanic Garden, in Edmonton, Alberta. Canada. Roger has published Edible Apples in Prairie Canada (Edible Apples to 1990: As Grown in the Canadian Prairie Provinces). Roger sent a complimentary signed copy of his book to our Alaska Chapter, NAFEX, in care of Erik Simpson. It has a wealth of information we will all find useful, and it shows top-rated and highly recommended apples and crabapples for the Canadian prairie provinces, where winters are long and harsh (sound familiar?). Thank you, Roger!