Spent potting compost

[Alvisona]

I've got a lot of tubs on the patio with bedding plants in, and I am replanting them now. What should I do with the old compost. Obviously I'm using new stuff for this years plants, but it seems a shame to throw away the old.

[woofgang]

you can toss it on the garden where it will improve the soil, or use it as a base layer in bigger tubs, topping up with new stuff. I actually leave my tub compost alone or quite a few years, but I use John Innes, not peat based or peat based substitute. All my suggestions assume that the soil is free of pests and diseases, Ie the plants that were in there didn't die of anything nasty.