Special Feature
“Apricots For The Midwest” Talk with Bob Purvis
From the Grapevine, March 2004
https://midfex.org/wp-content/uploads/2023/06/2004-1-March.pdf
One of the great benefits of being a MidFEx member, is getting to hear specialists talk about their area of expertise and also to participate in MidFEx field trips. This past month, Bob Purvis of Minnesota was MidFEx’s guest for the weekend of February 21 and 22, 2004. Bob spoke to us on growing apricots in the upper Midwest at the CBG on the 22nd. If you missed it, you missed a very informative session. In addition, the questions and answers were well worth hearing. The following are his introduction and a few excerpts from his talk. Bob shared with those present what he had learned over the past 17 years with observing and growing apricot varieties in Alaska, central Washington State, and now east-central Minnesota. He has been collecting the observations of members of the interest group living in various states and using them to make recommendations to amateur fruit growers as well as testing and evaluating varieties in his yard in Cottage Grove, near St. Paul, MN, a marginal Zone 4 location.
Apricots do best in areas with uniformly cold winters, brief springs and warm or hot, dry summers. Among stone fruits, they are usually the first to bloom, rendering them vulnerable to spring frosts. They do poorly and are often unproductive in wet climates because of disease pressure. Alternating freeze and thaw cycles in the winter can “de-harden” apricots and result in trunk injury if they break dormancy prematurely. Long, cool springs, as are found in western Oregon or Washington, are likewise unfavorable. When the trees set a crop, it is always “feast or famine”, with far more fruits set than the tree can adequately nourish or size. The strict cultural requirements for the fruit (a dry continental climate) are met in only a few states: California, Utah, and parts of Oregon and Washington. Many of the old apricot varieties are susceptible to brown rot and other diseases, and some of them to pre-harvest drop. The newer varieties described below now make it possible to grow apricots in many other parts of the US with fair to good odds for a crop at least some of the time.
The general requirements for apricot trees begin with site and soil considerations. An ideal site should have well-drained soil (not heavy, wet clays) and good air drainage (not in a valley or a low spot where the cold air collects), and full sun. Apricots, like peaches, require good sun exposure for best flavor and tree health, but they do not require high temperatures to develop full flavor. They require much less nitrogen fertilizer for adequate growth than peaches and have good tolerance of drought and slightly alkaline soils. A north- or east-facing slope may be a good site if it delays budbreak in the spring. Windy conditions are unsuitable for several reasons: drying out of the flower buds in the winter, hindrances to honeybees or other pollinators in the cool temperatures of early spring when apricots bloom, and premature dropping of fruit.
Commercial nurseries propagate apricots by planting “liners” of Manchurian apricot in the spring and then T-budding or chip budding them in early to mid-August with buds from the current season’s growth. Bob has had fairly good success bench grafting Manchurian apricot with dormant scions in March or April. Apricots can be whip-and-tongue grafted like apples, but the after-care of the grafts are more demanding. The roots of the freshly made grafts need to be kept in moist medium, such as potting soil, compost, or possibly sawdust because they will quickly initiate new hair roots. The grafts themselves need to be kept at 65 to 70° F and in a humid environment to promote rapid callusing of the graft union. The best solution is a 5-gallon bucket with a few holes in the bottom, with a plastic laundry bag tied over the top to hold in humidity. The bag should not touch the new plant tissue growing from the scions. Once a graft has initiated growth, it should be planted in a pot with soil, after being acclimated to ambient humidity.
Breeding programs have been established by organizations such as Agriculture Canada (at the Harrow, Vineland, and Morden research stations), the agricultural experiment stations of Cornell University in NY, Rutgers University in NJ, Washington State University, and by the USDA Agricultural Research Service. Some of the cultivars developed by those: programs are now offered by commercial wholesale and retail nurseries or may be obtained through members of NAFEX or the California Rare Fruit Growers. One of the most important lessons Bob shared with the group was what he has learned about varieties suitable for the Midwest. On a visit to Tree-Mendus Fruit, a large orchard with commercial apricot production in Eau Claire, Michigan, Bob noted that Harcot and Goldrich were the “bread and butter ” of the operation, well adapted to southwestern Michigan, but the operation was also growing Goldcot, Hargrand, Harglow and Harogem, all of which are good for fresh eating, canning, or drying. Herb Teichman, 73, the owner of the operation, told him that the apricot varieties developed for the western U.S. had not performed as well there as those from Harrow, Ontario (this illustrates an important principle: many apricots are adapted only to certain regions of the U.S. or Canada). On the other side of Lake Michigan, at Sturgeon Bay, WI (Door County), Dr. Dick Weidmann of the research station there mentioned that the most reliable and productive apricot variety was Orange Red (introduced as NJ32), which he said was hardy to at least -25°F. Although Harlayne is considered the hardiest of the Harrow selections, Harcot was the best performer there.
At the home of the late Bob Kurle in Hinsdale, IL all of the Harrow introductions performed creditably, even after wjnter temperature in the mid -20s °F.; and at Aspers, PA, mature trees of all of the Harrow apricot varieties were able to tolerate -28°F while fully dormant and produce a full crop the following summer. Because of their high fruit quality, self-fruitfulness, tolerance or resistance to common diseases, and resistance to fluctuating winter temperatures, the Harrow selections would be a good place to begin if you were planting only a few apricot varieties. Goldcot is acceptable for fresh eating but offers in addition a strong-branched tree that is precocious and an excellent pollenizer of other apricots (it is also the only named apricot to have fruited in Anchorage, Alaska although there are others that are probably better adapted to that cool, modified-maritime climate.
Jerseycot, an early-ripening apricot developed by Rutgers University, bore a crop 20 years of 22 in central New Jersey, and has also done well in central WA and in Indiana. It appears to be hardy in Zone 4 in Minnesota. The tree is very reliable; the fruit, medium-sized, sweet and mildly aromatic. Unfortunately, Jerseycot is too soft for shipping and is not being offered by commercial nurseries at this time. A few members of the apricot group are growing it. Alfred, introduced in Geneva, NY in 1965, has been very productive in central Wisconsin (NAFEX member Glen Stephen’s home) and Mississippi. Although the fruit is flavorful, it is small and can be only marble-sized unless the tree is thinned. Afghanistan, once offered by Southmeadow Fruit Gardens in Michigan, has done well in central Wisconsin and was cited as “my best performer” by Philip Rainville, a NAFEX member in central Massachusetts. Both Alfred an Afghanistan are well worth a trial in Zone 4 and possibly sheltered locations in Zone 3.
Another apricot from central Asia is Supkhany, a midseason sweet, white apricot with low acidity. It is evidently a late bloomer and was cited in a 1988 article, “Cold Gold”, in the Canadian edition of Harrowsmith magazine, as being winter-hardy. Supkhany is presently fruiting in San Marcos, CA and is under trial in southwestern MN. From the comments made in that article, Bob ventures that Supkhany is probably hardy in all of Zone 4 and worth trial in Zone 3. No one knows, however, its disease tolerance.
Several other apricots deserve mention here. Puget Gold originated in wet location in western Washington State. Bob grew Puget Gold in 1989-99 in eastern and then central Washington. The tree is self-fertile, strong, and resistance to spring frosts and fluctuating winter temperatures, as well as to disease pressure. The yellow-orange fruits come ripe in late July, with fine-grained flesh that is firm and sweet. They areevery bit as good canned or dried as they are for fresh eating. A few commercial apricot growers in the Yakima Valley have called it “the finest apricot we have eaten.” Puget Gold has shown itself adaptable to conditions in Maine, Delaware, and western Pennsylvania and as such is worthy of trial in zone 4b to 7. It has not been tested in Minnesota. Another Washington State introduction, Tomcot, ripens early but can get up to 2 inches across. Tomcot has been reliable in producing in northern Virginia and Wyoming and is produced commercially in central Washington. It is fairly resistant to spring frosts but is more productive with cross-pollination from another variety. Evidently it is able to withstand the hot, humid weather in Virginia without disease doing a lot of damage to it.
Within the past two years the USDA has released two new apricots from the Fresno, CA research station. Apache is an early-ripening, aromatic eating apricot of high quality; Nicole ripens slightly later. Apache survived -19°F and cold, drying winds in east-central MN in the winter of 2002-03 for Bob and may be worth trying in the warmer parts of Zone 4. Nicole shares high aromaticity and a vigorous, upright growth habit with Apache but was introduced in 2003 as an industrial (processing) apricot ripening in the Castlebrite season (early-mid season) in California. Both of these are self- incompatible but will cross-pollenize one another. Their suitability for the Midwest is yet to be determined.
Growers in Zone 3 have been testing and evaluating four varieties from the Prairie Provinces: Brookcot, Debbie’s Gold, Morden 604 (M.604), and Westcot. These all have proven themselves capable of cropping after exposure of the flower buds to -42°F. Brookcot is small, tangy, but late- blooming; Debbie’s Gold is vigorous and very cold hardy and tangy. Morden 604 is less vigorous, producing the biggest (2″ across in Canada) and sweetest apricots of the four but it is also the earliest to blossom, Westcot, nearly as sweet as the M.604, has become popular in Manitoba province, and like the others is self-fertile. These four varieties are well worth planting in Zone 3, but they are not well adapted to humid areas of fluctuating winter temperatures, in Bob’s opinion, in Zone 5 and warmer.
As these new varieties become offered by more nurseries and are more widely tested, growers in the Midwest will have many more choices than the standard ones offered in the past, namely Goldcot, Moongold, Sungold, and Moorpark. Bob said that the ultimate goal for him and the apricot interest group is to find apricot varieties that are suited for not just California or Washington but for most regions in the U.S., and to let others know how to acquire them. For further information 0n the apricot interest group of NAFEX, write to Robert Purvis, 7300 Iden Avenue South; Cottage Grove MN 55016.
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