This has been discussed to death & always creates differences of opinion - sometimes strong. You can search this forum with the search words reuse soil a find enough to keep you very busy for a while.

There is no one to tell you what you can/can't should/shouldn't do, but you're generally better off if you look into the future and ask yourself if your soil is going to collapse 10 minutes after you plant in it, or if you can be sure you can water properly and the soil will still hold ample air for the expected duration of the planting. If you can answer yes to the watering and aeration, you're good to go. If you cannot, you'll assuredly be sacrificing varying degrees of vitality and yields on the alter of convenience or frugality ..... but that's still an individual choice for you to make.

Al

Go nuts! It depends on the soil you are using. I created my own mix based on Al's (the previous poster) mix which is called 511. This is a sturdy mix.

First off, I would not do this with soil that has been previously planted for a year.

I use the soil no more then one year, and when I reuse, it is for vegetables. I never plant similar plants in that soil. Exanple, for fall, I plant tomatoes, in spring I might plant lettuce. Something that does not share common diseases. I shovel the soil and loosen it up.

After a year, I poor the soil on the lawn and start all over. I have tomatos, peppers, lettuces and so forth in second season soil now which are all doing superb. Rotation is key.

Not sure if I would do this with miracle grow or some other store bought soil If you did, you could just ammend the soil with some new soil. say 25% new to 75% old.

Soil is not cheap and I hate to be wasteful anyways. I have had plenty of success reusing soil. Like I said, after a year, that soil gets raked into the lawn. And my lawn loves it! I do not spend extra money for fertilizers. I also have about 15-30 containers that are 5-10 gallon each. So it is allot of soil.

If anything, try it out for yourself. :) If we give you a fish you can eat for a day, learn to fish, you can eat for a lifetime! :)

Enjoy

Bark-based mixes are not only sturdy and cost-efficient, they are also the perfect
mulch for lawns (as Linchat mentioned), gardens, outdoor plantings, et cetera!

Some of my plants are grown in Al's Gritty mix - 1:1:1 - and so I do sift and
re-use components from this mix - namely the quartz gravel and other stone ingredients.
Pumice - which can hold fertilizer/salts - can be soaked in warm water before re-use.
I don't think it's much of a problem, though.

Josh

We keep a tall rubber garbage can on the patio, with wheels, and at end of season, dump old, used potting soil in it. To this I add grass clippings, crushed leaves, whatever may be leftover in the garage in partial bags - peat moss, manure, vermiculite, etc. and mix it up. It's not scientific, but by spring there's a ready supply of potting soil and everything seems to thrive.

FWIW - What you're making is compost, which is a very water-retentive soil or soil component. I applaud you for finding a way to make it work for you, but I would caution others that if the mix you described was used as a soil or as a major fraction of a soil, it would be quite likely to bring problems to a high % of container gardeners.

Al

I think the questions to ask are... how long is the plant going to be grown in the container? And how much do you care about the plant and its health and vitality?

If we're talking about annuals or vegetables, a one season plant, then any long term results won't really be seen within the time frame the plant will be ensconced in the choice of soil and the pot.

However, if the planting is intended to be long term... meaning more than a single growing season, then I would opt for using a fresh, more inorganic, porous medium.

Compost is wonderful for growing in the ground... but I agree with Al... it's too fine and too water retentive to be of much use for container growing, and especially if we're talking about long term plantings.

I grow all my Flowers, Fruits, and Veggies (except wild flowers) in containers with moderate degrees of success. I plan growing 5 different varieties of highbush Blueberries in wine half barrels in early spring using Al's 511 Mix.
I would also like to try grow my tomatoes (greenhouse) in Al's 511 mix. My question is: Is there any additional soil component I should add to the above mix, apart from the normal use of fertilizer....? I compost all my garden waste (veggie - flowers - kitchen - lawn - leaves) along with my used potting soil. Thankyou Al for sharing your knowledge.. At 76 I've been gardening in various degrees for many years, and I'm still in kindergarten...Thanks again

I think you'll be better off if you add your compost to the garden & beds & stick to something that drains well & holds onto it's aeration for the whole growing season. The 5:1:1 mix will do that, though you could probably substitute compost for the peat component & expect similar results. Wishing you the best of luck!

Al

I can't believe I'm just graduating kindergarten for gardeners, myself! But there it is. I, too, have gardened my entire life with varying degrees of success... but thanks to Al and others here, I'm finally on the road to real success!

Good luck with your growing, everyone... the season is over for me outside, but the indoor season is just getting off the ground! My indoor bulbs help me maintain winter sanity!