The old potting soil from last year's flowerpots can be reconditioned and reused. This is a guide about reusing potting soil.
Here are questions related to Reusing Potting Soil.
Is there any way to revive old dirt in pots left out all winter?
By Jodee H from St. Louis, MO
By Karyn  01/06/2009
I always use the soil on my lawn to fill in holes that may have developed. Works great when added with some grass seed.
By marion davidson  01/09/2009
I either put it in my compost bin or put it in the bottom of pots and top up with new when transplanting plants to bigger pots.
By kathy  03/12/2009
I keep a 5 gallon pail with a cover to dump used soil in. I put in cut up chunks of fruit and veggie peels, egg shells, etc. Each time stuff is added, either stir or shake up the whole pail. When 1 pail is 3/4 full, start another...just keep adding used soil and "scraps" as you have them. You're actually composting in miniature.
I use this to fill about 1/2 of the next pot I want to use, put in the plant, then fill to desired level with new soil. Much cheaper than using all new soil, uses "garbage" as fertilizer"/compost, and it's basically free.
By nhe  04/19/2010
Of course. I pool all my soil from last year's annuals in a pile, add peat moss and fresh potting soil as needed, and find that I usually only buy one small bag of new soil each year. Make sure your pots stay outside all winter so they get nice and chilled to kill off bugs or diseases, and make sure all your pots drain well. I inherited some pots without drainage and while every bulb in them rotted, the soil was okay after mixing with peat and new soil.
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