Buying commercial compost can be a nightmare. Some growing media bring on seed and seedlings beautifully - nearly as well as your own home mix - and others are disastrous. You often wrongly blame yourself and, because of a failure, may have missed a variety’s optimum sowing slot.

You can never be absolutely confident any product will definitely perform well, but some pointers help improve the odds.

Does the print on a bag look clean and sharp or is it faded - a sure sign it’s an old one. Is it unusually heavy, suggesting it got wet by being kept in the open, resulting in nutrient loss. If you are buying a type recommended by Which? Gardening, does the label match the one in the magazine? If not it may be a different formulation so may perform quite differently.

It’s always worth checking out the test results from trials conducted by Which? They can and do vary from year to year, but some manufacturers consistently score pretty well and always produce reliable material. You may have your favourites, but it’s worth noting that the Melcourt, Miracle Gro, Pete’s and Levington are usually a good bet. Again, the quality of different mixes within a brand may vary a little.

Some brands are more readily available than others, so when looking at a particular league table for seed sowing, potting or general use, make a note of the best 3 that suit your wishes and affordability.


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For seed sowing, top performers this year are: For Peat’s Sake Eco Coir Compost, Fertile fibre Original Seed and Coco & Coir all purpose.

Young plants: Miracle-Gro Peat-free Plant and Grow, Coco & Coir All Purpose and Melcourt Sylvagrow.

For tubs and hanging baskets: Melcourt Sylvagrow Tub & Basket, Pete’s Peat-free Multipurpose and Melcourt Sylvagrow with added John Innes.

If you’re rightly concerned about environmental and social issues, you could check out the Responsible Sourcing Scheme (RSS) website. It has been set up in association with the Horticultural Trades Association and Growing Media Association and has the support of many leading producers like Miracle Gro, Westland, Melcourt and Levington.

The RSS checks out the amount of energy and water used in production, social compatibility - whether child or very low paid labour were used, the production’s impact on wildlife habitats and biodiversity, pollution levels and responsible efficiency of the production process.

You could compare the RSS and Which test results.

Finally, do buy local. Many garden centres sell 50-litre bags of peat-free for £8 or £9.50, 25-litre for £6 and there are multi buy offers. You’ll be hard-pressed to find the same compost for less than £12.99 in a mail order catalogue.

The Herald: Primula marginata ‘Prichard’s Variety’Primula marginata ‘Prichard’s Variety’ (Image: free)

Plant of the week

Primula marginata ‘Prichard’s Variety’ has pretty lilac blue flowers with a small white eye. These grow on sturdy stems that arise from mounds of foliage. The grey-green leaves are serrated and grow in rosettes. Like most primulas it prefers moist, but not soggy, soil and a fairly open position.