Hi Laura - since you are growing in containers I assume you are using a soiless container mix rather than actual soil, correct? If not, please do and you'll have much better success. If so, then yes, you can reuse at least some of it if the plants were healthy. The usual recommendation one sees is to replace at least 1/3 of it with fresh mix each year.

Several brands are recommended through out posts here - some are pre-packaged such as Pro-Mix and some are blend-your-own mixes of peat, compost, vermiculie, etc. No dirt. Dirt and containers don't grow well. ;) You'll find several recipes discussed on the Container Gardening Forum too.

You can just dump all the containers in pile, stir in new bags of mix well, and refill the containers. Not sure how you would sort it out of the pile of leaves, plants, etc. where you dumped it tho. I just pull the plants and leave the mix in the container until time to make fresh come spring.

But yes, some diseases will carry over in the soil so if you had serious problems it would be best to start fresh.

Hope this helps.

Dave

Thanks for the advice.
You are correct that it is container mix. This year i'll mix it with some new. Anything to save a few $$$