We have raised garden tables (off the ground, with proper drainage holes). I've added plenty of compost and peat moss to the top soil, but every spring I still have dense soil and moss grows on it. Not enough aeration, I'm guessing. Would perlite help? What about sand? Would peat moss make it worse and retain more water, or does it need more? What should I do?
Perlite would definitely aid in aeration of your soil. Extremely sharp sand would also help, but if weight is a consideration, perlite would preferable.