There are blackberry canes popping up all over my garden. Some of these things are about 10 feet away from the raised bed that the plant is in and some are even invading my other beds.
One runner even decided to spring up in the middle of my red onions. That's just not right. Come on, leave a man's red onions alone. Since the main plant is very close to my fence, my neighbor totally must have some in his yard now too. Ooops.
I was going to add, "Build root barrier" to my list of things that I don't have time to do but after some research, I've found out that blackberry runners can go down a meter deep. Yikes!