Plant blackberries from root cuttings you take during their dormant winter season. Make sure that all root cuttings are the size of a pencil.
Dig a hole three inches deep in well draining sandy soil. The pH level of the soil must be between 4.5 to 7.5.
Lay the blackberry root cutting horizontally in the hole, and cover it with dirt. Space the separate root cuttings three feet apart. Early spring is the ideal season for starting blackberries in Texas.
Bury drip irrigation lines at the time of planting to ensure your new blackberry plants get plenty of water. Turn on the irrigation after planting and let it run slowly for six months, then water your blackberries once each week.
Apply small but frequent amounts of fertilizer high in nitrogen around the base of the plants after they bloom.