We are frozen solid up here so my two tumbler bins (which have hardly ever worked) are rock solid. I have been saving kitchen scraps in buckets outside, also frozen. But I don't what to just throw them away. I figured in the spring I could dump them in the barrels along with shredded brown stuff (we have a grinder) and the leaves that I dumped by the bagful all around the garden since I didn't have time to grind them up also. I would love to have a three bin system built on the ground out of pallets or such. Maybe this spring I can talk DH into building one on an asphalt pad we have. I have read it doesn't hurt the bins to sit on a solid base.