The launch marks the first time Titchmarsh has supported a peat-free product.
Waitrose is 700 per cent up on last year with its gardening range after increasing the number of 'pods' from which it is selling gardening to 140 from 40 this March.
Waitrose launched its garden range with Titchmarsh in March 2013.
Other new launches include 16 grow your own products. Raspberry, strawberry and rhubarb plants are going best, with single season crops such as potatoes going less well, said product development manager horticulture Chris Wood.
The 30-litre compost retails at £3.50.
A new Waitrose Bee Mat is £10 and Butterfly Mat is also £10. Onions, shallots and seed potatoes are £2.50. The fruit plant range is also £2.50.
Wood said quality is more important than price to Waitrose.
A new cut flower herbaceous range will launch in April, supplied by Farplants.
See more in Horticulture Week magazine's 4 April edition.