New canes are produced each year from roots or the base of old canes. The floricanes need to be removed each year after harvest, but the new primocanes, which will fruit the following year, need to be thinned and trained. Selecting a Site Blackberries produce best in full sun, but they can tolerate partial shade. However, plants do not grow or produce well in heavy shade. It's best to avoid selecting a site where potatoes, tomatoes, peppers, eggplant, other caneberries, or strawberries have grown within the past 3 years.
Blackberries are sensitive to wet soils.
Therefore, drainage is an important factor to consider when you're selecting a site. Plants do best in a well-drained, fertile, loam soil with moderate water holding capacity. Avoid heavy clay or sandy soils. So it's important to rotate these crops from one site to another. Blackberry plantings aren't rotated often, because they live for a long time.