Recycling Soil

[Darkhorse]

   In the unfortunate situation that you have a plant that dies, have you thought about trying to recycle your potting mix?  I use HVH potting mix, and until now have been throwing away dead plants with all the soil in the pot.  I don't want the risk of passing on fungus or other disease/insects to my next plant, but I don't like the idea of tossing otherwise perfectly good soil.

   I've heard about boiling or baking potting mix to sterilize it, but this would also remove any beneficial microbes that are present in the mix.  The soil from HVH comes as a living mix-- would there be a way to add the living element back into the soil after sterilizing?  Or an alternative that I'm not thinking of that would allow re-use of soil without the risk of harm to the next plant?

[Charlie]

You could reinoculate it with worm castings and let it sit for a week before planting in it. I don't usually encourage reuse of soil or pots (they can be cleaned and sterilized with bleach if need be) but if you want to try it I would at least try to refresh the population of beneficial microorganisms.

Charlie

[Darkhorse]

Thanks, Charlie.  I do reuse pots because I have either clay pots or nice ceramic pots that I don't want to discard due to a lost plant.  I had been putting them in a bathtub full of hot water and bleach (90/10 solution).  Leave them in there for a few minutes and the bleach should kill anything that may be lingering on the pot.  Don't do it in clothes you like very much, though.


I may try that with the worm castings and see what kind of results I get.  I don't have any soil left and I need to pot up most of my plants so I ordered more.  Hopefully no more will die on me too soon. 

[Charlie]

In summer you can also "solarize" the old soil by spreading it out on concrete or some other non-soil surface and covering it with a clear plastic sheet. Make sure it is airtight, more or less, and the sun will heat the soil up to a temperature that will kill most pathogens.

Charlie