Using up old compost

End of season leftover bags At the end of the season we all end up with part-used bags of compost somewhere in the garden shed. It’s tempting to carry them over into the spring and for some applications this is perfectly sensible. Potting up bulbs – and there is still time even in January if you have unplanted bulbs sitting around – is a perfect way to use up remaining stocks. See our video on how best to do this at

Other useful ‘use-ups’ are topping up raised beds and veg plots. This adds a useful organic matter boost in readiness for the season ahead.

But when it comes to the all-important matter of seed sowing, which for many gardeners marks the start of the new gardening year, we would thoroughly recommend using fresh compost to ensure the best results. 

Why does this matter? Most peat-free composts, unlike peat, are at least in part made with composted materials. These always, just like the garden compost heap, contain a myriad of microbes which can impart wonderful benefits to plants growing in the media. But they can also feed on the nutrients in the mix and cause imbalances. The older the compost the more likely that this effect could impact compost performance. With extended storage time also comes the risk of the compost drying out (so always ensure that bags are well closed up after use), getting wet (so always store under cover) and even colonization by fungus gnats.

Use-by dates on bags At Melcourt we believe we are unique in that we state the date of manufacture on our bags. This helps gardeners to judge the age of the compost at the time of purchase and also once home, to keep an eye on when it should be used up. Our recommendation is that is it always best to use compost in the season of purchase, but failing that, within a year of its manufacture.

So, there’s no need to waste last year’s unused compost but keep it for the less exacting garden applications and always aim to start the new gardening year with lovely fresh compost – and remember – fresh compost is always best!