What to plant in lava rock
I have a narrow bed between my house and patio that I would like to utilize. I am imagining an edible low growing perennial. I have considered blackberries, which do well in my area. But they all seem to get very tall. I have also considered blueberries. But I'm not sure if they would like the environment in the lava rock. The rock goes about 4-6 inches down. There is black plastic below that. I'm not excited about taking the plastic out, so I would like something that wouldn't mind. I certainly can (and have in the past) add gardening soil on top of the rock. But it eventually filters down into the rock. I am successfully growing Wandering Jude there right now. But I would like to replace it with an edible. What are your suggestions?