The exchange rate has made it more expensive to import trees
Christmas tree growers say they are working flat out to deal with a surge in demand for British trees caused by a weaker pound.
The cost of imported trees has risen by an estimated 30% this year because of the pound's value compared to the euro.
One grower on the Gower, near Swansea, warned that there could be a shortage of Christmas trees this year.
The British Christmas Tree Growers' Association said there was an enormous demand from garden centres.
Association secretary Roger Hay said: "As a result of the value of sterling falling relative to the euro and the Danish krone, trees being imported this year are about 30% more expensive than they were last year.
"Not many trees are being brought into this country.
"I've been in the association now for a number of years and I've never known a year such as this for the demand from garden centres for trees."
A couple of big retailers in London wanted 3,000 trees, desperate to pay any money for the trees
Robert Morgan, Gower Fresh Christmas Trees
Robert Morgan, of Gower Fresh Christmas Trees in Three Crosses, Gower, said he had just under 200,000 trees on his farm, but was having to turn down orders.
"This year we're not wholesaling many trees at the moment because we're trying to keep up with the demand ourselves," he said.
"The last few days we've had orders from garden centres... a couple of big retailers in London wanted 3,000 trees, desperate to pay any money for the trees.
"Basically, they've left it too late and they haven't got the trees so there will be a shortage, but hopefully the British crop will suffice."
Mr Morgan said he also believed many individual customers were keen to buy trees that were grown locally, rather than imported.
"I think the customer is far more interested in where the tree comes from, as in the meat industry: where does the chicken come from, where does the meat come from?" he said.
"I think they want to know where it's come from and, buying from a British grower, you're assured of that.
"Also, when it's cut, it's obviously a fresher tree."
Many of those buying trees at the farm said they were keen to support local businesses.
Julia Minney, buying a tree with her husband Gareth, said: "I grew up in Three Crosses so it's quite important to me to have a tree from somewhere really local.
"The more we can do for the environment the better, and we think getting a local tree from Three Crosses is doing our bit for the environment."
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