How Many Blackberry Bushes Can You Put in One Pot?

Pot Size

• Use a pot that is at least 12 inches across and 12 inches deep. Ideally, to avoid hindering blackberry bush growth, your pot should measure at least 2 feet in each direction. This is for one blackberry plant. If you want two or more plants, your pot needs to be at least 3 to 4 feet long and 2 feet deep. In addition to the pot size, ensure that your pot has drainage holes in the bottom so the blackberry bushes will not get waterlogged.

Spacing

• If you have multiple individual pots with blackberry bushes, space them so the centers of the pots are about 3 feet apart. If you need more than one row, leave about 10 feet between the rows of pots to provide adequate air circulation around the plants. If you are planting multiple bushes in the same pot, leave a minimum of 2 feet between plants. Ideally, you should have a full 3 feet between plants. You can plant two bushes next to each other in a long rectangular pot measuring about 4 feet by 2 feet or plant three bushes in a circular pot with a 4-foot diameter.

Soil

• When you grow blackberries in a pot, you need to ensure that the soil is as close to the ideal growing conditions as possible. Lining the bottom inch of the pot with large gravel or small pieces of broken pots helps increase drainage. Choose loose potting soil with compost mixed into it. The soil pH should be between 6.0 and 6.7. Take a soil sample to your local garden center for testing and add lime to increase the pH or sulfur to decrease the pH. Subsequent years, apply about 1/4 lb. of fertilizer per plant in the late spring or early summer. Spread the fertilizer over the soil around the edges of the pot, keeping it at least a foot away from the stem if possible.

Plant Type

• Opt for the erect, bush-style blackberries when growing in pots. These plants have stronger stems and do not require trellising, which is difficult to install in or next to potted blackberry bushes. Some of the best thornless erect blackberry cultivars are Arapaho, Navaho and Apache. If you don't mind thorns, options include Kiowa, Chickasaw, Brazos and Choctaw.