The approval is also unusual in that Okanagan, which is based in Summerland, British Columbia, is a small company. Most genetically modified crops are developed by giant seed and chemical companies like Monsanto and DuPont Pioneer.

Neal Carter, the president of Okanagan, said the apple had “a lot of silent supporters” and would be popular with the food service business. “I can’t believe how many requests we’ve had just this morning to our website from people who want to buy trees,” he said. The roughly 45 investors in the privately held company include many people in the apple business, he said.

Image Neal Carter, president of Okanagan Specialty Fruits. Credit Okanagan Specialty Fruits

It will take a few years for Arctic apples to be widely available because trees have to first be planted and then become mature enough to bear fruit.

Mr. Carter said that four growers would plant a total of 20,000 trees this spring, covering a mere 20 acres or so. From 5,000 to 10,000 pounds of apples are expected to be ready by the fall of 2016, enough to provide samples to food service companies and other potential buyers. The product could reach stores, in very small quantities, in 2017, he said.

Documents released by the Agriculture Department on Friday suggest the decision to approve was essentially made last May. Mr. Carter said he thought political factors had kept the approval from being announced. He said the company, which had initially requested approval in 2010, finally became so frustrated that it wrote a pointed letter to Secretary of Agriculture Tom Vilsack last month.

A spokesman for the Agriculture Department said it took time to analyze the issues and all the comments received. There were two public comment periods that together drew more than 175,000 comments, the overwhelming majority opposed to approval.

Consumer and environmental groups, who say that genetically modified crops in general are not thoroughly tested for safety, were highly critical of the decision on Friday.