Homebase is selling £4.99 'Etoile d'Amour' poinsettia buy one get one free until 24 December.
Homebase horticultural buyer Martyn Hill said: "We have a good working relationship with The Sun and have worked together to offer a variety of horticultural promotions for the keen garden and home enthusiasts that read their gardening page.
"The promotion runs up until Christmas Eve, so it is too early to say at this time how the response has been to the poinsettias plant offer currently running. However, last year we received several thousand redemptions on the same offer and we expect to achieve that again this year."
Sun gardening editor Peter Seabrook said: "UK growers now have a longer, slower, energy-efficient growing programme, producing sturdier, short-jointed stems, which hold their leaves much better in centrally heated rooms."
He added: "It's best to buy British. They don't travel well in dark lorries. Dutch growers also tend to use smaller pots, making them top-heavy and shorter-lived indoors."
Pinetops owner Derf Paton said: "This was a great success for Homebase. The promotion has really lifted its footfall. I've got ideas for another promotion for next year too."
Many publications have been quoting HW's figures of 4 million poinsettia sales this Christmas, with more than half coming from the UK.
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