I’v got 4 of those already. But they’ve been used. So, they have their share of weeds which were never removed last year (after my accident shut me down from gardening).
Here’ what I did to one of mine that got weeds because I didn’t plant anything: I covered up the weeds with newspaper and card board, and soil on top, planted seeds and watered well.
It kept the weeds out for the season.