Dunelm chief executive Will Adderley is the son of Bill and Jean who founded the homewares retailer in 1979.
He took over the running of the 142-store business again in September. He plans expansion to 200 stores, and for online and home delivery.
A representative speaking at Dunelm’s inaugural Garden Press Event stand last week, said: "Gardening is a seasonal thing for us. We’re here because we’re looking into doing more gardening.
"We sell bbqs, lawnmowers, garden furniture, accessories - everything bar plants and seeds. The online business is booming."
Gardening launches on 16 March at Dunelm. Products include lanterns from £14.99 and dining sets from £99.99-£399.99.
Revenue in the first half of the year to 27 December increased by 14 per cent to £406.4m with like-for-like sales up 6.2 per cent.