I have a small corner garden of moon-plants that return each year via the many seeds that fall from the pods each fall. I also have weeds mixed in with the moon-plants. If I lay a few inches of mulch over the garden in early spring to stymie the weeds, prior to the moon-plants starting to grow, will the moon-plants still grow or will the mulch stymie them also? Thank you for your time and assistance. Regards, Gary