Does unopened compost keep indefinitely?

aliasojo

My garden plans have had to be shelved.

I recently bought around a dozen different bags of compost and top soil. All big bags of good quality stuff that cost a fair bit.

So, do they have a shelf life or will they keep indefinitely? I'll be gutted if they aren't able to be kept.

a1cat

They last forever

Sambucus_Nigra

They might go a bit mouldy inside but are still useable.

valk_scot

Keep them somewhere dry and on a solid surface, like a shed or garage and if that's not possible, put them om top of an old pallet to get some air underneath, and cover them with a tarp. Compost bags usually have air or drainage holes so the worms can get into them, water can penetrate and the compost can go wet and slimey and grow maggots etc. It's still fine to use this sort of thing on beds and in pots of course but it makes it unpleasent to handle. Best to keep it dry.

savemoney

They should be fine kept dry

peter_the_piper

a1cat wrote: »

They last forever

Not quite correct, they may well last into next year, kept as suggested, but the chemicals in the compost slowly react with each other and change.

aliasojo

peter_the_piper wrote: »

Not quite correct, they may well last into next year, kept as suggested, but the chemicals in the compost slowly react with each other and change.

I expect it will be next Spring/Summer before I am in a position to be gardening again so was hoping to keep till then.

A._Badger

peter_the_piper is right - some of the fertilisers used in potting composts can change and interact over time. I have heard it said that this is a particular problem with traditional soil-based composts, like the various John Innes formulae but I've seen no hard evidence to support this.

In practice, if you buy your compost early in the season there's no guarantee that you're not getting 'last year's' anyway, but, personally, I wouldn't want to keep it for more than, say, a year, even properly stored.

Top soil I wouldn't worry about.