Containing raspberry runners.
I have a raspberry row that is about 7 ft away from a row of blueberry plants. To help keep the weeds down, there is a 4 ft wide strip of landscape fabric with 5" of wood chips on top between the rows. The Boyne raspberries are sending runners under the fabric and they are coming up among the blueberry plants. I think that I will have to install a vertical barrier in the soil between the rows. The rows are just over 60ft long. Is my best option to rent a trencher and install vertically a 12 inch strip of aluminum roof flashing? Is there a better or easier way to form a barrier? Is 12" deep enough? Is aluminum flashing thick enough to be a decent barrier or is some other material better?