What do you do with old potting soil?
I have a bunch of pots with just potting soil left over from last year. I'm trying to clean up and get ready to transplant a bunch of new stuff and I'm wondering what can i do with my old potting soil? Most of the left over soil is from failed transplants or seeds that didn't take or plants killed by frost. No real disease issues.
Can I re-use? Can I put this in raised beds I grow veggies in? or should i just sprinkle it around? or should i throw it away (that would be a shame, this stuff can get expensive)?
thanks for any suggestions, or maybe just tell me what you do.
I dump it out of the pot into a wheelbarrow or whatever -- and examine the inside of each empty pot as a do so. I am looking for evidence of mold or salt build up. If there is significant salts, I'll rinse it and then add a bit of liquid gypsum. If there is mold, I will spray it with a light amount of Lily-Miller PolySul and mix it in. It can then go immediately into a planting bed, or be used to pot a healthy plant after being allowed to sit for a day and watered one more time. For seeds, I use sterile medium.
If the potting mix is just old and tired and I'm sure there is no disease or other pests involved I spread the mix into my garden. When I know the soil is diseased or contains pests it goes into the garbage. Potting soil may be expensive but killing expensive plants with diseased plants is even more expensive.