The TV gardener said: "I'm trying to raise standards of horticulture and to reach more people. I grew up with and still support nurserymen and specialist nurseries but you can't turn your back on a big part of the potential gardening community."
Titchmarsh, who will front new BBC series Alan's Garden Secrets, to be broadcast this autumn, added; "I'm working a lot on information going out to customers to educate their staff in terms of horticulture.
"I thought long and hard about signing up with B&Q. But they reach more potential gardeners than any other outlet in the country. What I have tried to do in 30-odd years on the box is to try and raise standards in horticulture and to reach more people. The more people less intimidated by their garden the better to reach their potential."
Lifesize cutouts will appear in every B&Q store and he will make guest appearances in stores this season. He will also write guidance leaflets for customers of the garden centre/DIY chain's 330 stores.
B&Q horticulture manager Steve Guy predicts a 30% rise in grow your own in 2010 after a similar rise in 2009.
See more in HW 29 January.
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