Tuesday, September 1, 2009 8:28 AM EDT
Question: "At the end of the growing season, what do you do with the soil in your balcony containers? Can it be re-used?"
Answer: I’m all for recycling and I have been reusing my container “soil” for years. The only time I don’t reuse it is if the soil in the container is densely packed with roots. Then it goes off to the compost heap. In the fall, I often just leave the soil in the containers (if they are the type that won’t crack during the winter deep freeze) until next season. Then, in the spring I dump the old soil into a wheelbarrow (if you are in an apartment, a large plastic tub works).
I sometimes pour in a kettle of boiling water to kill any nasties that may have wintered over. But, I admit I’m not vigilant about this and sometimes don’t bother; though it’s probably good insurance to do it.
I always refresh the soil by mixing in about 50% new potting mix. Never use soil directly from an outdoor garden. Garden soil is too heavy and gets compacted in a container, preventing the plants’ roots from moving freely and obtaining the oxygen they need. As well, there’s a risk of introducing bugs and bacteria. If the mixture seems like it could use a little more "lightening" up, I'll add some peat moss or vermiculite. Then, I add a slow release granulated fertilizer. How much depends on the size of the container. You should check the label for the appropriate amount. I pot up my plants as usual.
The garden centers, of course, recommend new soil every season. And why wouldn't they? They are in business to make sales. In all my years of gardening I've never had a problem reusing container soil.
Answer provided by Veronica Sliva, Regional Director, Garden Writers Association.
This column was originally posted on the Foodnetwork.ca Eating Well site.
Gardening Advice is featured on Style Sheet on Tuesdays.