Great article! I use
Promix and it is usually pretty dry when I get it, unlike bags of potting soil and similar products. I have used it after sitting around for a few years, and it worked identical to a freshly purchased opened bag. On a similar note that sort of backs up what the original article claims, I had a bale of
Promix that got wet. It didn't get soaked by any means, but the outer wrapper was opened and water got in, making everything damp. The
Promix also had a slightly musty smell afterwards, so there was mold/mildew present to some degree. I found that the plants grown in the opened/damp bag of
Promix showed slower growth than a fresh or older dry bale. Since
Promix doesn't have much in the way of nutrients to begin with, the effect was notable. I think
Promix is sterilized prior to shipping, and the dry nature of it helps to keep the shelf life long and extended, but for any soil or medium that has any degree of water in it, this is something to keep in mind.