Which? Gardening magazine’s annual growing media survey is well-known for springing a few surprises – and this year’s is no exception.

Biggest of all is that Westland’s peat-based Jack’s Magic All Purpose compost achieved the highest test score in the category for composts for seed raising, beating five specialist seed composts as well as other multi-purpose rivals.

The Jack’s Magic score was 73%, and earned a Best Buy recommendation, along with three others on 70% - Levington Original Multipurpose, B&Q’s Verve Multipurpose Peat-free and Westland Multipurpose with John Innes.

Westland’s Gro-Sure Seed & Cuttings Compost scored just 20% in the trials and was tagged a ‘Don’t Buy’, along with Homebase John Innes No 1 Seedling Compost and Waitrose & Alan Titchmarsh Peat-free Compost.

For raising young plants, Miracle-Gro All Purpose Enriched Compost (50% peat) scored an emphatic victory with 95%. In second place was Verve MP Peat-free on 88%. Ironically, Verve Sowing & Cutting Compost scored better (by 2%) in this category than it did for seed sowing. Ten products received ‘Don’t Buy’ advice

For plants in container, there were three Best Buys, with FertileFibre’s coir-based MP Compost leading the pack on 86%, closely followed by Melcourt’s peat-free Sylvagrow on 84%. The third was Levington Original MP (80% peat). Carbon Gold’s Gro-Char All Purpose (peat-free) emerged the best of the rest, on 69%. There were nine ‘Don’t Buy’s.

The seed raising trials were on tomato and pansy seeds; raising young plants on basil seedlings and pelargonium young plants. For containers plants, a patio potato crop was assessed, plus the vigour and flowering of begonias.