Blackberries are a very easy fruit to grow. However tempting, do not grow blackberry plant unless you are certain they are virus-free since viruses are a widespreade problem with blackberries. Select high quality plants from a nursery with a good reputation
Climatic And Ecological Requirements Of Blackberries:
Altitude: 1250 – 2200 east of the rift valley.
Temperatures: – 10 – 300C
Well distributed 1200mm. Where rainfall is less than this irrigation is necessary at 25mm/week. The crop does not tolerate drought. Irrigation by drip increases the yields, improves the size and appearance of berries and prolongs the harvest period.
Grows on wide range of well drained soils. Although, deep sandy loams, rich in humus are most ideal, with good moisture retaining capacity. The drainage should be sufficient to keep the water level at least 80 – 100cm below the soil surface. The ideal soil pH range is 5.5 – 6.5. Avoid saline soils.
Varieties of Blackberry plant:
Early – ‘Brazos’ ‘Cherokee’ and ‘Comanche’
Late – ‘Black Satin’ ‘Smoothstem’ and ‘Thornfree’
Hybrid – ‘Boysenberry’ ‘Loganberry’ and ‘Marionberry’
Site Selection for Blackberry plant
The Soil should have the following characteristics to enable the blackberry plant to bears more fruits such as, air drainage, water availability, the previous use of the site, labor availability. While blackberries are adapted to a wide range of soils, the best blackberry soils are well drained and of sufficient depth (about 2 feet). Soil testing is critical in evaluating a site for blackberry plant
Land Preparation for Blackberry plant:
The first step in site preparation is to layout the planting. Erect thorny and erect thornless cultivars are commonly planted in rows 8 to 10 feet apart, while trailing thornless cultivars should be planted in rows 10 to 12 feet apart
Site preparation should begin at least a year before planting. Three main factors are included in site preparation:
Adjusting soil fertility and pH,
Building up soil organic matter,
Eliminating perennial weeds.
Any perennial weeds such as johnson-grass, bermuda-grass, multiflora rose, or wild brambles present on the site should be eradicated with herbicides prior to planting
Soil samples should be taken from the plowed planting strips, and the soil should be sampled to a depth of 12 to 18 inches.
A suitable cover crop should be planted to reduce erosion in all worked areas. Bluegrass, orchard grass, or perennial ryegrass work well as permanent row middle. Sudan grass can be used as a warm season green manure in the planting strips
Planting Blackberry plant
Blackberry plants and hybrids are all self-fertile.
Select a site that receives full sun if possible for best berry production.
Soil needs to be fertile with good drainage. Add organic content to enriched your soil.
Make sure you plant your blackberry plant far away from wild blackberries that may carry viruses.
For semi-erect cultivars, space plants 5 to 6 feet apart.
Space erect cultivars 3 feet apart.
The Space trailing varieties 5 to 8 feet apart.
Space rows about 8feet apart.
Planting may be done in late fall, however, it should be delayed until early spring in very cold areas as it could kill some hybrids
Trellising and Pruning Blackberry plants:
Trellises should be constructed for blackberry plant.
For trailing varieties, explore a two-wire system, running a top wire at five to six feet with a second line 18 inches below the top wire. After the first year, there will be fruiting floricanes along the wires. Train the new primocanes into a narrow row below the fruiting canes.
Directing all canes in one direction may make it simpler.
After the fruit harvest period, the old fruiting (floricanes) are removed to the ground. However, unless there is a lot of disease, it’s best to delay removing the old fruiting canes until they have died back considerably.
This allows the dying canes to move nutrient back into the crown and roots. After old fruiting canes are removed, train the primocanes up on the wires .Work with one or two canes at a time in a spiral around the trellis wires. Canes from adjacent plants may overlap a little. No pruning of primocanes is necessary.
In areas with low winter temperatures, leave the primocanes on the ground for the winter where they could be mulched for winter protection.
In the spring, after damage of extreme cold has passed, train the old primocanes (now floricanes) up on the wires. Avoid working with the canes in cold weather, as they are more prone to breaking.
Erect blackberries produce stiff, shorter canes that come from the crown and root suckering (forming a hedgerow). At-trellis works well to support erect blackberries.
Erect blackberries require summer pruning.
Remove the top one to two inches of new primocanes when they are four feet tall. This causes the canes to branch, increasing next year’s yields. This will require several pruning sessions to tip each cane as it reaches the four foot height. Primocanes (suckers) that grow outside the hedgerow should be regularly removed.
In the winter, remove the dead floricanes (old fruiting canes) from the hedgerow. Also shorten the lateral branches to about 1½ to 2½ feet.
With primocane-fruiting erect blackberries, cut all canes off just above the ground in the late winter for the best fruit
In the summer,when the primocanes are 3½ feet tall, removed the top 6 inches. The primocanes will branch, thereby producing larger yields in the fall.
Semi-erect blackberries are vigorous and easier to manage on a( Double T Trellis) . Install four-foot cross arms at the top of a six foot post.
Install a three-foot cross arm about two-feet below the top line. String high-tensile wire down the rows, connecting to the cross arms.
These blackberry plant need to be pruned in the summer. When the primocanes are five feet tall, remove the top two inches to encourage branching.
This will require several pruning sessions to prune canes as they reach the height.
In the winter,remove the dead floricanes (old fruiting canes). Spread the primocanes (new floricanes) out along the trellis. Canes do not need to be shortened. However, they can be if they are difficult to train.
Mulching is important throughout the season to conserve moisture and suffocate weeds. Keep a thick layer of mulch surrounding plants at all times.
The roots may keep sending up an abundant amount of shoots (canes). Keep order by pruning away the majority of them so that the survivors can produce lots of berries.
Irrigation for Blackberry plants:
Blackberry plant growers contemplating commercial production must have a reliable source of irrigation water. As a rough guide, blackberries require 1 to 1 1/2 inches of water per week from rain or irrigation from bloom time to harvest. After harvest, adequate soil moisture is still necessary to promote good cane growth, but in most years post-harvest supplemental irrigation may be necessary only during prolonged drought.
Fertilization application for blackberry plants
The soil nutrients most needed by blackberry plant are nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg). In most instances, nitrogen is the only nutrient that must be applied on an annual basis.
The application of other nutrients should be based upon the results of soil and foliar tests, which should be submitted every two years after planting, and the health and vigor of the plants
Weed management in a blackberry planting begins during pre-plant site preparation. All perennial weeds should be removed from the site, either through the use of herbicides or through tillage.
Cover cropping the soil for at 19 least a year before planting will reduce the number of annual weeds after planting. The planting design of most blackberry plantings creates two distinct areas of weed management, the planting row and the area between rows (row middles).
Trailing thornless blackberries are maintained as separate plants within the row. Hoeing, mechanical cultivation, mulching, and herbicides are effective weed controls with this situation. Upright thorny and thornless blackberries form a continuous hedgerow. The density of the hedgerow canopy suppresses weed growth
Anthracnose (fungus – Elsinoe veneta):
A common cane and foliage disease of blackberry sometimes called dieback
The disease first appears in the spring as small purplish spots on new shoots and purple bordered spots on leaves. Spots on canes enlarge, usually develop an oval shape, and gradually turn gray
PESTS AND DISEASES
- Raspberry Borers
- Fruit Worms
- Gray Mold
If your plant is suffering from the blackberry disease known as raspberry bushy dwarf virus, the leaves will have some bright yellow on them, and the leaves of the fruiting vanes may have a bleached look in the summer. The disease known as blackberry calico will cause faint yellow blotches on the leaves of the plant.
Harvesting of Blackberry plant:
Blackberries are primarily harvested by hand, either by pickers, pick-your-own customers, or a combination of the two.
Mechanical harvesters are available, but blackberry plant that are harvested mechanically are only suitable for processing
Blackberries are ready to harvest when sweet, fully colored, but still firm. Harvest during the cooler parts of the day. Fruit is best picked directly into the sale container to minimize handling
Storage of Blackberry plant:
Harvested blackberry plant should immediately be placed in the shade and refrigerated as soon as possible.
Although fresh fruit is always best, blackberries can be stored by canning, preserving or freezing.