Describing Prime Minister David Cameron’s official London residence as “the greyest frontage known to man”, the Ilkley-born TV presenter and gardener said he would even return every season if needed to plant new blooms in the urns.
He made the promise at a conference organised by the Royal Horticultural Society, which is trying to reverse a trend towards paving spaces outside homes for parking and ease of maintenance that has left millions of front gardens without any plants.
The RHS, which is running a “greening grey Britain campaign”, argues that front gardens filled with plants improve people’s well-being, help wildlife and air quality and reduce the risk of flooding in towns and cities.
While flowers could be seen as “fripperies” and “insignificant” in comparison to global issues such as climate change, the urns would be a reminder people can make a difference by growing plants, Mr Titchmarsh said.
“Our British Isles are a patchwork quilt in which gardens play an important role. When joined together they make something altogether larger, more important and more influential than the sum of their parts.
“If each of us did our bit in that tiny front garden, we really could make a difference, not only to our environment where clean air and flood water drainage are vitally important, but also to our spiritual well-being,” he said.
“When the Prime Minister returns from the next conference on climate change, I suggest he invests in a couple of statuesque urns, handsome in shape, classy in design, capacious in stature, and positions them on the doorstep of No 10 Downing Street - the greyest frontage known to man.”
He told the conference: “These urns, well planted, their occupants changed to suit the season, will be a daily reminder of all our responsibility to the natural world around us.
“They will be seen on cameras across the globe, a gesture from the British - supposedly a nation of gardeners - that nudges us in the direction of making a difference rather than simply talking about it.”
Suggesting there would be a “fly in the ointment” of the Treasury refusing to pay for the urns, he added: “I’ll put my money where my mouth is, I’ll buy them and I’ll even come and plant them up, every season if need be. That’s a promise.”
Responding to the offer, Communities Secretary Greg Clark, who also spoke at the summit, said: “Thanks for Alan’s wonderful suggestion to the Prime Minister, I will put it directly to him.
“And the offer of Alan Titchmarsh to plant your pots outside your front door is not something that everyone gets, so I’m sure he’ll be thrilled to hear that.”
Mr Titchmarsh acknowledged people needed a place for a car and their wheelie bins outside their homes, but argued that the wheels of a parked car only took up a space the size of a pocket handkerchief.
The rest of the front garden could be planted with fragrant thyme and other low growing plants, while pots at the front door could be filled with flowers that are beneficial to butterflies and bees, he said.