Buying soil for future ?

[Steve705]

My grow is almost finished but I’m not going to start up another grow again till the end of winter. I want to buy some promix HP ahead of time but I’m not sure if it’s a good idea to buy it and then let it sit around for a while in the unopened bag. Is this ok to do? Thanks guys

 

[az2000]

I don't think you'll ever know how long it sits in a warehouse (the last bags I bought weren't dated). I add 1-1.5 tablespoon Fertilome Hi-Yield Agricultural Lime to every gallon of mix. (I add 25% more perlite to Pro-Mix HP's 35% when I grew entirely in it. So, I added that amount of lime to that mix. I may have done only 1 tablespoon then because it was less peat.). That would protect you if it's sat outside and undergone some condensation cycles, and the buffering is exhausted. To be safe, you could test the ph of a bag before using it.

A few months shouldn't be a problem. But, if there's no reason to buy it now, it might be better to wait till closer to when you want to buy it. See Premier Horiculture's explanation. (<<link).