Incredicompost is 80 per cent peat and is only available by mail order, priced at £14.99 for 70 litres bag plus 4.99p&p.
T&M say "increaded public disappointment in exisiting products in the market" has led to the launch. It added: "We were shocked at the difference between best and worst composts available." It said cheap composts and those wwith "a high percentage of local authority-supplied waste are a false economy for gardeners".
Horticultural director Paul Hansord said: "We've been unhappy with the majority of consuemr composts for several years now. So have many of our cusotmers, who through no fault of their own have problems with T&M plants because of the compost they have used."
Adverts on the Ideal World shopping channel said: "The best 'value' compost that for all your growing and gardening needs. Suitable for all seed sowing, taking cuttings and potting on, indoor and outdoor use."T&M will include a 210g sachet of incredibloom fertiliser with each bag bought. Petersfield (W.E Hewitt & Sons) is the compost supplier.