Can I Reuse Soil From My Vegetable Pots?

Q: I plant my tomatoes, cukes, and squash in pots on my deck. I’ve pulled the plants, getting rid of all the roots, etc. Can I reuse the soil? 

A: Unless you had problems with the leaf diseases on your plants last year, there’s no reason not to reuse the old soil. As you probably noticed, natural decomposition reduced the volume of that soil. The average particle size is a little smaller now. This will reduce the internal drainage characteristics of the soil. To fix this, use perlite to mix with the old soil to restore its original volume.