HelpfulGardener.com

I have some potting mix, maybe now 5 years old, I grow flowers and herbs for the wife at the back door on the deck, I am noticing it is not holding the water for as long as it was in previous years. Can I dump it in the compost bin or is best to toss it out, leaning towards composting, but figure I'd ask the experts.

By all means, toss it on the compost pile. The humus in the old potting soil has completely decomposed and needs to be replaced. You can simply mix some compost into it, if you have some around. It might help to mix in some perlite, as well.

Tossing the old soil on the compost pile, however, helps to cleanse it of disease-causing organisms, without actually sterilizing it.