Climate Needed to Grow Blackberries

Best Climate for Blackberries

• Blackberries grow best in warm, temperate climates. They are less cold hardy than raspberries. The plant flowers from May onwards making them vulnerable to frosts in northern areas. Avoid planting them where cold winds will damage the canes. Windbreaks are a good way to reduce cold air movement that can reduce fruit production.

Cold Weather Problems

• According to USAGardener, blackberries are hardy in USDA zones 5 to 10. The erect variety of blackberries are more cold tolerant, but you can also grow trailing varieties in colder regions if you lay mulch over the canes in winter. Winter winds can break the blackberry canes, so windbreak protection is advisable. Late frosts can damage blossoms and reduce fruiting.

Hot Weather Problems

• According to North Carolina State University, blackberries can suffer sun-scald from hot weather. Plants require additional watering during this time, but keep in mind that blackberries do not tolerate very wet soils. Hot temperatures also inhibit plant growth and fruit size. Maintain good air circulation around plants to minimize disease and pest problems.

Site Preparation for Blackberries

• Blackberry plants prefer full sun and good drainage. Add some organic matter to soil to provide aeration and water retention. The soil should have a pH of about 6.0 to 6.5. Blackberry plants prefer sandy or loamy soil conditions. If grown in wet sites, set the plant in raised beds to provide adequate drainage. In mountainous areas where winter weather can be severe, plant the blackberries on hillsides to avoid cold damage to the canes. Avoid planting on south slopes which warm first in the spring and where frosts can damage early-opening buds.

Cultivation of Blackberries

• Erect types of blackberries require training during the first year of growth. Semi-erect and trailing varieties do not need this immediate training, though they do require support as they begin to grow. Generally, only a small crop is produced during the first year. All varieties need pruning, cut out old canes after they finish producing fruit and keep plants compact. You can also grow blackberries from cuttings in 15-gallon containers, in a light soil mix that absorbs water well. Shallow-tilling compost into the soil will aid in healthy growth.