The appeal will allow 5,000 children to benefit from Greenfingers gardens. Greenfingers has built 49 gardens and plans more at Ipswich, Luton, Oxford, Horizon House in Northern Ireland, Winchester, Grimsby, Dartford, Balloch, London and Sunderland.
Ashley said: "At Greenfingers we are acutely aware of the need for us to continue providing hospices with amazing spaces for children with life-limiting conditions." He added that he wants more businesses and individuals to hget involved with fundraising.
Director Deborah Skillicorn said: "Many hospices have woefully inadequate outside areas."
Ashley takes over from Matthew Wilson and the new appeal replaces the £750,000 Rosy Cheeks appeal.