“It’s Blackberry Time!”
Blackberry time has finally arrived – so most of us are thinking COBBLER. In Missouri, gardeners and market growers are especially lucky to have the largest blackberry breeding program in the world right next door. Dr. John Clark from the University of Arkansas directs the University of Arkansas blackberry breeding program. The breeding program was established by Dr. James N. Moore over 45 years ago.
To make the blackberry crosses, researchers select two blackberry parents that have specific desirable traits. They then take the pollen from one to fertilize the ovaries of the other. The seed that results the cross is planted, grown to mature plants, and evaluated. Berries that look and taste good and hold up well in shipping are selected for further evaluation. If one of the progeny from the cross is exceptional, it is chosen to become a named variety. The goal of this program is to produce varieties with larger berries that will produce through a longer growing season in Arkansas. Of course, if you can get rid of the thorns along the way, even better.
In fact, there are several thornless erect blackberry varieties to choose from including a good choice for home gardeners – Ouachita. However, if you would rather brave the thorns, Chickasaw and Kiowa are good choices. Both are high yielding and have large berries.
Blackberries are perennial plants and have a root system that lives year after year. The above ground canes, however, are biennial and only live for two years. The first year canes that arise are called primocanes. Most blackberries fruit the next year when the cane survives the winter and is called a floricane. The most limiting factor for blackberry production in our area is winter hardiness. The Arkansas varieties lack hardiness in the upper Midwest and are best suited to southern and central Missouri. However, in 1997, the University of Arkansas discovered that that some blackberries bear fruit the first year on the primocanes.
This is good news for more northern areas where the blackberry floricanes are not cold hardy enough to overwinter. The primocane fruiting varieties can bear a crop even if the floricanes are damaged by winter cold. That is because the primocanes grow and fruit in the same season and do not need to overwinter. If you manage the primocanes, pruning is done simply by mowing the canes down in the winter. The primocane blackberry varieties that have been released to date include Prime-Jim, Prime-Jan and Prime-Ark 45. All are thorny but all bear fruit on current season growth and yield has been recorded beginning in late July and August in Clarksville, Arkansas. Prime-Jim and Prime-Jan are home garden varieties, but Prime-Ark 45 has commercial potential as well.
For a list of sources for the Arkansas blackberry varieties, see http://www.aragriculture.org/horticulture/fruits_nuts/Blackberries/
Now that we have primocane fruiting varieties, “blackberry time” has been extended farther in the season as well as further north. This translates to more cobblers for all!
Direct comments or questions concerning this column to Marilyn Odneal via email at MarilynOdneal@missouristate.edu; write to Missouri State Fruit Experiment Station, 9740 Red Spring Road, Mountain Grove, Mo. 65711; or call (417) 547-7500. Visit our Web site at http://mtngrv.missouristate.edu.
