With fruit as big as your thumb, the blackberry has long been one of nature's most prized edibles, especially in Kentucky, where optimal growing conditions produce a flavor as sweet as the childhood memories people have of picking them. Today, Kentucky-grown blackberries are highly popular, and demand for their juicy, black-to-dark-purple fruit often exceeds supply in many parts of the state, said John Strang, extension horticulturist with the University of Kentucky College of Agriculture. “In Kentucky, people are pretty well keyed into blackberries, and it is an important fruit crop here,” he said. Strang said that the extent of the damage from a killing freeze in April isn’t known yet. Initially, he thought all of it may have been destroyed, but growers are starting to see blossoms appear on some varieties. According to Strang, the full extent of the damage won’t be known until summer’s heat sets in, which could cause damaged canes to collapse.While the vagaries of nature might spoil the plans of consumers and producers alike, in good years, the law of supply and demand for fresh blackberries, the official state fruit of Kentucky, does provide a prime opportunity for growers. There are only 110 to 120 commercial acres of blackberries in the state, with yields per acre averaging 5,000 to 11,000 pounds, depending on the type. No one knows how many backyard gardeners grow the fruit, but what experts like Strang do know is that total acreage devoted to blackberries is often not enough to meet Kentucky’s increasing appetite for them.“I think people like cobblers,” Strang said laughingly, as he tried to explain the blackberry’s popularity, “and blackberry jellies and jams.” Apparently, Kentuckians also like blackberry ice cream. Winchester-based ice cream company, Valentine’s, now sells blackberry ice cream made with Kentucky-fresh blackberries. And many Kentuckians appear to have grown fond of blackberry wine, Strang said.“We have about 42 wineries in this state now, and blackberry wine is an extremely popular wine. There’s a pretty high demand for blackberries to make wine,” said Strang, adding that such wine sells for a premium price.Blackberries, however, are more than just an edible – and drinkable – delight. They were used in ancient Greece as a cure for mouth and throat diseases and, during the Civil War, as a cure for dysentery. In recent years, research has shown that blackberries contain a good supply of antioxidants that may provide protection against cancer and other diseases. Additionally, they are a good source of vitamin C, with 1 cup of blackberries providing about half the daily recommendation. “Consumers take these things into consideration,” Strang said.From a production standpoint, blackberries are likewise appealing, not only because of the market potential but also because they grow and yield well in most parts of the state, Strang said. Blackberries need to be planted on a site with high elevation for added frost protection, and require good soil drainage. “There are several excellent blackberry varieties that are particularly well-suited for production in Kentucky,” he said. Blackberries are not a heavily sprayed crop in Kentucky, which also make them attractive to growers. Furthermore, they begin to bear fruit the second season after planting, and many varieties ripen over a long period of time, giving growers a “pretty good spread on the season,” Strang added.While people might remember braving prickly thorns in their quest for sweet, wild blackberries, Strang said a lot has changed since those “blackberrying” days of old. Two types of thornless varieties are thornless erect, which usually does not need support as it grows, and thornless semi-erect, which does need support. “If you like blackberries but do not want to contend with the thorns, there are now some excellent varieties,” he said. Ouachita (pronounced wa-chi-ta) is one of the new thornless erect varieties, a release from the University of Arkansas breeding program. Tests at UK’s Robinson Station near Jackson show that it survives well and produces a berry with excellent flavor, Strang said. It is also resistant to orange rust and rosette, two fungus diseases that can be problems in Kentucky. Apache is another of the newer thornless erect varieties and has been a top producer in UK blackberry trials. Apache has large berries that remain large throughout the growing season and an excellent flavor, Strang said. “Both Ouachita and Apache are very sweet, just about as sweet as the thorny berries,” Strang said.Of the thornless semi-erect varieties, Triple Crown is recommended, especially for growers who need to maximize production in small spaces. Triple Crown averages 20 to 25 pounds of berries per plant at full production, Strang said.“The (Triple Crown) berries are larger, contain at least 2 percent more sugar and are also less acidic than the other semi-erect varieties. However, the thornless semi-erect varieties also have the largest seeds of the three types,” he said.Still, he said, the thorny varieties of blackberries that most people are familiar with may be difficult to beat in terms of winter hardiness. They also have big berries and small seeds, which consumers typically like. Two popular thorny varieties are Chickasaw and Kiowa.“Blackberry flavor varies a little bit with the season. If we have cool, dry, sunny weather, you’re going to get really sweet blackberries. If we have cloudy, wet, rainy, hot weather, they’re going to be more tart,” he said.The month of May is the time to get new plants into the ground. With any blackberry variety, Strang “strongly” recommends getting virus-free plants from reputable nurseries. Irrigation is also beneficial, he said. “You want to obtain a soil test and get the pH adjusted and get your phosphorous, potassium and magnesium levels adjusted prior to planting,” he said.For a soil test or additional information about growing blackberries in Kentucky, contact your county extension office.