Keeping tree roots out of beds
I know that the problem of tree roots invading beds is a common topic around here. In my perennial beds I think it's a fact of life and I intend to adapt the plantings as our trees mature (which is certainly a wonderful thing overall).
But in our raised beds in the kitchen garden, I can put a liner at the bottom of the beds to keep the tree roots out. What would make an effective liner? Would weed blocker fabric be strong enough? What about window screen? Or both?
The trees in question are aspens and willows.
Last year was pathetic as I watched the plants in 2 of our raised beds wither all summer long, no matter how much water I gave them. So this spring I intend to take the soil out of the beds, put a liner in, and replace the soil. Sounds like an excellent workout, doesn't it? :)
Thanks for whatever wisdom you can share!