dealing with blackberries that came up wild and spread over large area

Question

After extensive storm damage to our home and gardens were dealt with (medical issues and cost delayed clearing the garden for 2 years), we found what appear to be blackberry plants growing throughout a large area. During this past season we let them grow wild as we rebuilt sheds, replaced fences and lighting, etc. The canes are tall and thick (many nearly 6 feet tall and a little more than 1 inch in diameter – with some serious thorns) and have spread out about 400 sq. ft.
1. Should we do late winter pruning of these plants?
2. We can leave some of these plants where they are, but many have spread into raised beds and paths. When can we dig up and transplant the “intruder” plants, which can be relocated to our front garden area?
3. Since these “wild” plants have thrived without any care, we assume we don’t need to “winterize” these plants, however, is that a safe assumption since the area is also overgrown with grasses and has a substantial buildup of dead leaves and grass?

Answer 1

Blackberries and other wild-type berry plants are vigorous spreaders. Keep that in mind when you relocate them. Canes that had fruit this year will not produce next year so cut those down. Canes that emerged this year will fruit next year. Your options for control of unwanted plants is to repeatedly cut them down, use an herbicide or dig them out. Here are the details: http://ipm.ucanr.edu/PMG/PESTNOTES/pn7434.html