By Richard Ashton
n a late spring day the blackberries are just starting to change color and, when they turn midnight black, it’s time to start picking and perhaps get the kitchen ready to put together a fresh blackberry cobbler. Or maybe it’s time to just eat some berries fresh off the plants. In years gone by and even today many people "can" the berries whole for use throughout the year. It’s not hard to think of the many excellent ways to use blackberries.
Wild blackberries can be found on many farms and ranches in Texas. They love deep sandy soil and are usually found growing in moist areas near a creek, spring or seep. The wild berries are not very erect and tend to be trailing. With time they may form a thicket. The cultivated blackberries are more erect and generally have larger stems, which are called canes. Wild blackberries have been the source of many a tasty blackberry pie or cobbler in late spring. The wild berries are small and it takes quite a few to make any kind of sweet dessert, but they are still mighty good. Today with all the hybrid varieties that have been developed by plant breeders, we have very large blackberries that produce heavily. The cultivated varieties of blackberries are well-adapted to most areas of Texas and are fairly easy to grow in home gardens. Variety selection is important for home production as some of the varieties do much better in one area than they do in another.
Scientifically, blackberries belong to the Rosaceae family, genus Rubus, subgenus Eubatus. They are also called bramble fruit. There are more than 400 species of blackberries in North America with the cultivated varieties grown in Texas being hybrids. The types of blackberries are generally grouped according to their growth habit, either trailing or erect. Trailing blackberries that grow on brush or shrubs in the wild are called dewberries. Cultivated forms of trailing types are boysenberries and youngberries. The major cultivated varieties are grouped as erect blackberries. The fruit clusters of the trailing types are open and not very numerous. The erect types have tighter clusters that are numerous and usually ripen later than the trailing types. Most cultivated varieties bear thorns, but in recent years thornless varieties have been developed that have become very popular.
Blackberries are perennial plants that grow canes in two-year cycles (biennial). The first year the new canes, called primocanes, grow vigorously but do not produce any flowers. The second year the same canes, called floricanes, do not grow any longer but produce flowering laterals with small leaves. The white-to-pale pink flowers are produced on the tips of the flowering laterals. The fruit are actually a collection of numerous drupelets which form the "berry." The drupelets form around ovules that are fertilized by pollen that is moved by insects, particularly honeybees. The floricanes die back after the berries are produced and are replaced by new primocanes.
All these erect thorned varieties have ‘Brazos’ in their heritage. It was developed here in Texas and has been the standard for blackberry production in Texas for years.
‘Brazos.’ Developed at Texas A&M University and introduced in 1959, ‘Brazos’ has been the Texas standard for years and is still a great variety. The berries are large and the plants produce heavily. Probably the most widely adapted blackberry in Texas and recommended for most of Texas, this variety starts ripening early, May 15 to May 30 depending on your location. ‘Brazos’ has good disease tolerance. It is interesting that ‘Brazos’ has some raspberry and wild dewberry in its heritage. The berries are a little acid and are better for cooking and canning than fresh eating. This variety has more thorny plants and larger seeded fruit than many of the improved varieties.
‘Rosborough.’ Another Texas A&M introduction that was released in 1977, ‘Rosborough’ is similar to ‘Brazos’ but the berries are firmer, sweeter and it has smaller seed than ‘Brazos.’ ‘Rosborough’ ripens about the same time as ‘Brazos,’ and is intended as a companion or replacement for ‘Brazos.’ A good early variety for east and south-central Texas, ‘Rosborough’ is not recommended for northwest Texas because of low winter temperatures. The flower petals are lavender instead of the normal white.
‘Womack.’ Released in 1977 by Texas A&M, this is the smallest of the A&M releases but still a nice size. It is firmer and better quality with smaller seed than ‘Brazos.’ The flower petals are lavender. ‘Womack’ ripens at the same time as ‘Brazos,’ and is recommended for west-central and north Texas in sandy areas. It’s not recommended for southeast Texas or northwest Texas.
‘Cheyenne.’ Released by the University of Arkansas in 1977, ‘Cheyenne’ has very large fruit that are sweet and have a slight raspberry flavor. ‘Cheyenne’ ripens about June 8, and is recommended for east Texas. It is resistant to orange rust and tolerant to several other diseases.
‘Chickasaw.’ Released by the University of Arkansas in 1998, Chickasaw is comparable to ‘Shawnee’ but has better storage and handling qualities and high yielding plants. This variety is recommended on a trial basis only because the area of adaptation has not been determined.
‘Choctaw.’ A 1989 release of the University of Arkansas. The medium sized fruit are somewhat soft, and storage and handling is sometimes a problem. The outstanding quality of this berry is its very early ripening time. This variety has a 300-400 hour winter chilling requirement. ‘Choctaw’ is hardy to -14 degrees F. and is a good candidate for the Panhandle.
‘Brison.’ Released by Texas A&M in 1977, ‘Brison’ has berries that are firmer, sweeter and with smaller seed than ‘Brazos.’ A very early ripening blackberry, it ripens about a week before ‘Brazos.’ Production is equal to or slightly better than ‘Brazos.’ ‘Brison’ is recommended for south-central Texas on blackland clay soils. The low chilling requirement precludes this being a good choice for far north Texas. It’s not recommended for southeast Texas because of fungal diseases.
‘Shawnee.’ Released by the University of Arkansas in 1983, this variety has a long ripening season. The berries are medium to large in size, are somewhat soft and do not ship or store well. The plants are highly productive. ‘Shawnee’ ripens about a week later than ‘Cheyenne,’ and is susceptible to double blossom disease.
‘Kiowa.’ This, the last of our thorned variety recommendations, is one of the best. ‘Kiowa’ was released from the breeding program of the University of Arkansas in 1995. The fruit of ‘Kiowa’ are the largest of the varieties listed here and are at least 1/4 bigger than `Brazos.’ These berries are six to eight times the size of wild blackberries. The berries weigh an average of 10 grams with a blocky oblong shape. The fruit is firmer than `Shawnee’ and stores and ships well. The fruit starts ripening about three days after `Shawnee,’ about June 4 in central Texas. `Kiowa’ is recommended for east, north and central Texas, but is not recommended for northwest Texas.
These erect thornless varieties can all trace their heritage back to the varieties ‘Merton Thornless’ from England and ‘Thornfree’ from the USDA breeding program. All are patented releases of the University of Arkansas breeding program.
‘Apache.’ Released in 1999, this is the largest fruited and highest yielding of the University of Arkansas thornless releases. The fruit are medium-large and ripen in early July in central Texas, late in comparison to the thorned varieties. The sweet berries are firm and handle well, and the plants are very erect. Recommended especially for northeast Texas but adapted to other areas.
‘Arapaho.’ Released in 1993, this is the earliest-ripening of the thornless blackberries. The medium-sized fruit ripen in the latter part of May to early June in central Texas. Not a high yielding variety, it yields about 60 percent the fruit of ‘Shawnee.’ The fruit are very sweet with small seed size, and ‘Arapaho’ is one of the best tasting blackberries. It is resistant to double blossom and rust.
‘Navaho.’ Released in 1988, this variety has medium sized fruit with high sugar content. A moderate yielding variety, ‘Navaho’ yields about 3/4 of the production of ‘Shawnee.’ It has a ripening season of about four weeks. With a high chilling requirement of about 800-900 hours, it is only recommended for north and northwest Texas. ‘Navaho’ is hardy to -14 degrees F. It is difficult to establish from root cuttings but grows vigorously when it does get established.
‘Ouachita.’ One of the newest thornless varieties released in 2003, the fruit are sweet, large and have good storage and handling qualities. Starts ripening about June 10 and continues for about 5 weeks. Production and size of fruit are comparable to ‘Apache.’ ‘Ouachita’ has a chilling requirement of about 300-500 hours, making it a good trial variety for central and southeast Texas.
‘Natchez.’ Released in 2007, with large, firm berries on a plant with high yields, ‘Natchez’ yields twice as many berries as ‘Arapaho.’ ‘Natchez’ ripens early, about June 1, and seems to have good disease tolerance.
Primocane Fruiting Varieties
The University of Arkansas in 2004 released the varieties ‘Prime-Jim’ and ‘Prime-Jane,’ new primocane fruiting blackberries. These varieties fruit on the first year primocanes. Unfortunately, they have not done well in Texas.
Growing blackberries is fairly easy but does involve some setup work and other considerations for best results.
Soil. Blackberries grow best in deep sandy soil, but any well-drained soil will work if the pH is in the range of 4.5 to 7.5. If your soil does not drain well, try growing the berries in raised beds.
Climate. The best climate for our southern blackberry varieties is anywhere in USDA cold hardiness zones 7 to 9, which includes most of our state.
Water. Rainfall or irrigation is needed every 7 to 10 days depending on how well your soil holds moisture. Many people use drip irrigation, and it is probably the best system for blackberries as the plants like lots of moisture but do not like to be too wet.
Planting. You can buy either plants or root cuttings to get your project started. Root cuttings are placed in a trench 2 to 4 inches deep with 2 to 3 feet between plants in rows that are 6 to 12 feet apart. The distance between the rows depends on what type of equipment you use to keep the row centers clear of weeds.
You can also purchase dormant bareroot plants in the winter for immediate planting at the same distances. Growing blackberry plants are sometimes available in containers that can be set out at your convenience.
Pollination. Insects are necessary for pollination of the berries. While honeybees are the best pollinators, many insects will visit the flowering plants. Most areas have enough pollinators for a home garden.
Trellising and Pruning. Pruning and trellising are probably the most important part of growing blackberries. A metal T post and wire trellis system is the most common way of handling the canes. You can also use any type trellis for just a plant or two.
Use metal 6-1/2 foot T posts, which you can get at nearly any farm supply store. Place them 15 to 20 feet apart in the row. Use two high tensile wires for attaching the canes, one at 2-1/2 feet above the ground and one at 4 feet above the ground. The wire is available at most farm supply stores as electric fence wire. Be sure to get the largest size with 12-1/2 gauge being the best. Attach these wires to the T posts using the wire clips that normally come with them or use any short length of wire to attach the wires to the posts. At the ends use a short metal electric fence post driven in the ground at a 45 degree angle. Brace your end T post ending your two wires at the ground with this angled post. Tighten the wire either manually or using an electric fence tightener.
If you set your first plants out in the winter you will need to let them grow a while in the spring and early summer. Then select the two strongest canes from each plant and cut any others back at the ground. Let one cane grow 3 to 4 inches above the first wire (at 2-1/2 feet) then cut it off about an inch below the first wire. Two side shoots should then grow out below the cut. Train the side shoots horizontally to the wire using plant twist ties loosely attached or use twine. You will need to do this a couple of times as the side shoots grow out. Use a pair of gloves when doing this even with the thornless varieties. Next, let the second cane grow until it is 3 to 4 inches above the top wire (at 4 feet) and then cut it back an inch below the wire and train the side shoots to the wire as with the first operation.
By training only two canes you will put all the plant’s energy into these canes and you will have bigger healthier plants that will bear better crops. Be sure to cut off any other sprouts that emerge from the ground.
The spring of the next year you should be set for a good berry crop. After they have fruited, cut the floricanes off at the ground and remove them. Then select two of the new primocanes and follow the procedure above. Every year you need to cut back the fruiting canes (after fruiting) and train and tie the new primocanes if you want bumper crops.
The common commercial trellis setup uses three or four wires on the T posts. Wherever they grown, primocanes are simply tied to the wires. This may be an easier method but when it comes time to remove the floricanes it is more work. The two wire system has been well tested and seems to work better.
Diseases. There are a number of diseases that affect blackberries. They include anthracnose, double blossom (rosette), orange rust, crown gall, powdery mildew, nematodes, strawberry weevil, cane borer, spider mites and stink bugs. To prevent damage from diseases, remove any wild blackberries from the immediate area, select only good quality planting stock, destroy any plants that show disease symptoms and remove the fruiting floricanes from the field after they have fruited.
Fertilizer. The first year a balanced fertilizer should be used after the plants show new growth. The following years only nitrogen is usually needed. You can apply the fertilizer as a narrow band along the row. If you can, get a soil test to determine your exact soil requirements.
Blackberry plants can be purchased at nearly any nursery or garden center in Texas. ‘Brazos’ is the variety that is most commonly found, but the other improved varieties are available at many nurseries.
Richard Ashton is the author of several books on fruit growing. The Incredible Pomegranate – Plant and Fruit, Jujube – The Chinese Date and his soon to be published book Sweet Cherries for Southern Orchards are available from Third Millennium Publishing at www.3mpub.com/ashton or they can be purchased through the Texas Gardener bookstore.