The old potting soil from last year's flowerpots can be reconditioned and reused. This is a guide about reusing potting soil.
Is there any way to revive old dirt in pots left out all winter?
By Jodee H from St. Louis, MO
I always use the soil on my lawn to fill in holes that may have developed. Works great when added with some grass seed.
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.
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.
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.
Do you have to use new potting soil every year when potting flowers? I usually do, but I didn't know if it was really necessary or not. Thanks.
Melissa from Charlotte, NC
Most of the good stuff will have been leached out by the process of watering and the water draining out of the bottom of the pot. I would either mix it with new or just get new soil each time.
By Robyn Fed
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 scrap 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. (03/12/2009)
If you have potting soil without combustible additives, pop the dirt on an old cake pan or cookie sheet and give it a whirl in the oven to sterilize it. Even works by putting a pan on the outdoor gas grill. Sometimes you need this to kill invading species of bugs, etc.
Or just go and find a spot in the veggie garden, scoop out old, scoop in new. I mix my own soils, using sand is very good, peat, black soils, etc. (03/12/2009)
I have outdoor planters that have had the same potting soil in them for at least 5 years. Every spring I break up all the soil in the planters and remove any large clumps of root or stem that did not decay over the fall and winter. Then I add my new plants and fill in with more potting soil as necessary. I have not had any problems with this method. (03/12/2009)
By Carol L.
I keep a large plastic storage tub near my potting area, this is old pot soil, new potting soil, and a little dirt mixed all together. I stir it all together in my wheelbarrow, then dump it in the storage tub with lid for ready soil. I leave it out in the hot sun, with lid tightly secure to heat and kill any bugs that might be in the old soil. Works year after year. (03/13/2009)
Never discard potting soil, it can be reused year after year. (12/30/2008)
As usual, I agree with MCW. You can reuse it. I find I need to use more plant food cause whatever it comes with has been used up, but the dirt is still good. (12/30/2008)
I keep a large container near my potting bench with a bag or two of good potting soil. When I discard a plant I just put the soil from that pot into this container. I then add peat moss, vermiculite (sp?) and compost and work it real well. I add some of the long lasting fertilizer like Osmocote when I re pot anything. Been working for quite a while! (01/05/2009)
Yes, you can reuse it. I always add new fertilizer when replanting a plant anyway. But, be sure to fluff--not sure how else to say it-- the dirt. Often it can get compacted and it sure helps the next plant to have the soil mixed up and fluffed ? Sounds funny- you get the picture.
Good luck. Lori (01/05/2009)
I always use the soil on my lawn to fill in holes that may have developed. Works great when added with some grass seed. (01/06/2009)
I usually mix it into the bag of new soil then just go from there. That way you have a fair mix of old and new soil. (01/06/2009)
You need to be careful when "fluffing" the soil, make sure you are wearing a mask and gloves.
Empty last year's soil from the pots. Add compost or manure to the soil. One bag of compost or 1/2 bag of manure to a wheelbarrow full of soil. Reuse the soil with your new plants.
To reuse seed starting mix, heat up the soil in the microwave to kill any fungus, etc. Make sure your microwave is in the garage or outside when you do this because it sure does smell, but you won't have the seedlings die off. (01/06/2009)
Yes, you can, and I have re-used potting soil. If you have any doubts that the potting soil in question is past the expiration date, or was previously used you can re-use it. Take your potting soil and spread it on a cookie sheet and put it in a 275 degree oven for about 20 minutes. If you think that there may be any parasites that need to be killed, spray the soil with a light misting of water and proceed the same way for 20-30 minutes at the same temperature. I've had great results using both methods. (01/08/2009)
I generally put new soil in when I am re potting plants, but put the old soil out in the garden so it doesn't go to waste. (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. (01/09/2009)
It depends on how long your plants have been in the potting soil. Unless the plant has only been in the soil for a short period of time, it has probably used up the nutrients in the soil. You can provide nutrients via additives to the water (Liquid Miracle-Gro is what I use), but if that isn't enough to keep your plants thriving, then you need to at least add in some new potting soil. I NEVER throw out the used soil. I just mix it into one of my outdoor flower gardens. Good luck with your plants!