Beware cheap compost in January salesDon't risk using old compost for your young plants

27 December 2013

Think twice before buying cheap compost with your cut-price Christmas lights, as it's likely to be old stock which won't be good for your plants.

Buying seed sowing compost at this time of year, however cheap, can be a false economy. 

Compost containing green waste in particular often deteriorates with age because the waste continues breaking down in the bag - just as it would on your compost heap. This upsets the nutrient levels in the compost, meaning your seeds and seedlings are likely to struggle. 

Ensure your seeds and young plants thrive this spring by using a Best Buy compost for raising young plants with the new 2014 packaging pictured in our review. Never buy compost with faded packaging even if it is a Best Buy as it'll be old.

If you're not a member already, you can get instant access to all our reviews - from compost, tomatoes and lawnmowers to coffee machines, TVs and washing machines - by signing up to try Which? for a £1

Which? compost trials

We've tested composts every year since 1985 and never cease to be amazed by how much the quality varies. 

This year we've tested 22 composts, including compost from top brands B&Q, J Arthur Bower's, Miracle-Gro, Westland and Verve to find the ones that will get your seeds and young plants off to the best start this spring.

No other organisation carries out such extensive and impartial compost trials as Which?. To find out more about the lengths we go to, read how we test compost.

Best composts for seeds and young plants 2014

This year, only four of the 22 composts we tested proved good enough to be Best Buys. Some are such poor quality that our seedlings struggled to survive at all.

To find out which composts you can trust this spring - and which you should steer clear of - read the full results of our latest compost trials.

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