Planter box help

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Weed block as I have used it in my yard comes in two types, tries to let nothing through, but seems to disintegrate really fast if it gets any sun, and the kind built to put on the surface, which holds up better, but can let weeds through. I'd think the more solid kind would work best in your case. As long as it is marked to have drainage. I also now use peanuts in the bottom of my half barrels, for a little more air, but with a solid bottom, I am not worried about weeds.

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