If a potting mix is made up of fine particles, such as mostly peat moss, most people I know of fail growing their plants in less than a year or so.

Simply put, the soil compacts, suffocates the roots or holds moisture far to long causing root rot..I just don't get why succulent and cactus plants are sold in peat mixes anyway? You should of seen all the dead ones they threw away of rot today at Lowes..I wanted to cry..They were so beautiful just a week ago, now all rotted!

That is why I rinse the soil off the roots of EVERY single plant I get as soon as I bring it home and plant it in a 5.1.1 mix or gritty mix..

I forgot to do this to a plant I bought from a nursery 3 weeks ago, and the thing croaked. You should of felt how compacted that soilless mix was..

Mike..:-)

By your rant, I must be fortunate indeed to have access to a potting soil which doesn't lose its structure for a good two years or more. I've had a lemon balm plant in one large pot in this soil for at least four years. Only this year has compaction really affected its growth.

Of course, I occasionally get bad batches, and then have to deal with repotting every pot that got that soil. Only oregano does fine no matter the compaction level. (And these batches were 90% peat, so when they compact they set like concrete.)