Garden Soil
A brief discussion on a cactus email list recently got me thinking about potting soil for cacti: to sterilize or not to sterilize. This is a topic that stirs passions.
For what it’s worth, I don’t use sterile soils in my potting mix, but I use “clean” ingredients. Thus, for small amounts of soil I use packaged potting soil (typically a loam with compost) as a base. I mix the base with coarse sand and with perlite or pumice. For general use I add each part in equal volumes. Because I use packaged and/or composted ingredients, I don’t worry about insect eggs or fungal inoculum, and I don’t heat treat the ingredients.
However, if I used soil right from the garden (as in the photo) I’d be sure to bake it for 2 hours or more at 200 degrees F (about 93 C) to kill insects and some pathogens. If I threw in a handful of compost (from the compost pile) and I wouldn’t bother to heat treat the compost because I’m happy with the “cleanliness” of composed ingredients.
Other folks feel differently about the matter and don’t take special efforts to kill organisms in their potting soils, heating or composting. I guess that, whatever works for you is what you should do.
written by: jshaw at opuntiads.com
