When people refer to a sterile potting mix, what do they actually mean? I am potting on my maples grown from seed last year using a mix of multipurpose compost and vermiculite to improve drainage, but presumably this will not be a sterile potting mix? Am I risking introducing disease by not using a sterile mix? Nicola
generally a soilless mix (peat, perlite, vermiculite and maybe volcanic rubbble or pumice) that has been cooked or otherwise sterilized to lessen chance of pathogens and weed seeds being present in the growing medium. Until three seconds after you open the bag and put it in the non sterile pot in the great outdoors. :)
Nicola, using a top class, fast draining commercial potting soil which is NOT sterile has not hindered the hundreds of seedlings I grow. These seedlings know how to grow; they have not read our books and are not limited by our "knowledge". Have fun with your seedlings; I do.
