Nearby tree farms and suppliers have reported running out or running low on trees weeks out from Christmas.

Christmas Tree Keng, which is the closest farm to Canberra at 30 kilometres away, sold its final tree last Wednesday.

Visitors to the 30-acre property choose their own monterey pine and borrow a saw to fell the tree and take it home. But owner Keng Tan said he had a rush of people come to buy trees early this year.

"Normally we go another week, [but] there's been a huge demand so what do you do," he said.

He didn't want to disappoint loyal customers, but said to sell any more would start on next year's stock.

Ziggy Kominek from Santa's Shaped Christmas Trees, a 200-acre farm in Gundaroo, said he had enough trees for another week or so.

"It's actually been a fantastic season [for growing]." he said.

Even a local tree delivery company is close to sold out; The Christmas Tree Truck had to look interstate for trees this year.

"We get our trees from Gundaroo, he didn't have amazing supply this year so it was tough for us," co-owner Liam Zeller said.

He had noticed an increase in demand for real Christmas trees around Canberra.

"The industry is growing, pardon the pun. What we've noticed is a culture of people changing back to real trees from fake trees."

Another supplier, Canberra Christmas Trees, had posted on its website that it would not be supplying Christmas trees in 2015, perhaps influencing demand on other suppliers.

A real Christmas tree will set you back somewhere between $50 and $150, depending on the tree's size and whether it's delivered.

With proper care and plenty of water, they should last about a month after being felled.