It's not so much a nationalistic stance as a tacit acknowledgment that the Christmas tree, once alien to Mexican tradition, is here to stay.
For centuries, the centerpiece of the Mexican Christmas was the Nativity scene. Trees didn't come until the 1940s, along with Santa Claus and reindeer, and have since become hugely popular.
Criticized as a cultural invasion, the trees were also long thought to be environmentally damaging, because in the early years many were cut illegally in the pine-covered mountains surrounding Mexico City.
Now, with legally registered tree farms sprouting in Mexico, authorities sense an opportunity to create jobs and sustainable use of woodlands. So they're urging people to forgo the Douglas and Balsam firs from Canada and the U.S. Northwest, and buy Mexican.
"In four or five years, this market can be ours, and then we can start exporting," said Environment Secretary Alberto Cardenas.
Mexico imports around 1 million trees per year and grows only 500,000 domestically. But under government-supported programs, growers are getting support payments and seedlings of local fir varieties like oyamel and acahuite.
Since the 1990s, the government has been tagging and certifying legally harvested trees. It gives farmers about $240 an acre to start tree plantations that will mature in five to eight years.
Roberto de Dios Garcia, who heads an association of 32 tree farmers, says Christmas trees can be grown on small plots, help prevent soil erosion and boost income for poor farm families.
"We plant on plots that were mainly old farm or pasture land, some badly eroded and some that simply weren't producing anymore. Some couldn't even grow grass," Garcia said. "Now they have a permanent forest cover ... families can come out and see the trees, and spend time among the trees."
The industry has become so popular that when a group of Masagua Indian women protested over water rights, officials offered them thousands of Christmas tree saplings as a development project.
This year, officials are hoping to sell trees with 'cut-your-own' programs at farms in Mexico City's mountains, just high enough to catch a light snowfall in some years.
But will homegrown trees catch on?
"My customers still prefer the imported trees because they last longer. They don't dry out as fast," said Juan Torres, who has sold Christmas trees at a Mexico City market for more than a decade.
Cardenas counters that domestic trees have a fresher scent.
There are other disadvantages.
"The Mexican trees don't have that nice, traditional Christmas tree shape," said Torres, the tree vendor, miming the conical shape of his Oregon trees. "They sprawl out more."
Such larger cultural issues seem to permeate the local market in a middle-class Mexico City neighborhood, where strings of blinking Christmas lights, fake icicles and Santa figurines compete with traditional Nativity figurines and poinsettia plants.
"Maybe this is all becoming a little 'gringo-ized,"' said government employee Ricardo Martinez, as he and his wife looked over imported trees at a Mexico City market. "But that's OK."
Torres said customers often put up both a Nativity scene and a Christmas tree. Mexicans are, after all, masters at cultural blending. Indian, Spanish and North American traditions all find a place in the mix.
"People buy the traditional stuff, the Nativity scenes and the farolitos (painted paper luminaria), and they also buy the Santas," said market vendor Mercedes Rodriguez Navarette, whose table was overflowing with both. "And then they make a nice mishmash out of it all."