It's not just Christmas promotions that are creeping earlier. With temperatures still above 80 degrees in many areas and the official last day of summer two weeks away, fall is already here—in the form of pumpkin-flavored foods.
Starbucks started offering its popular pumpkin spice latte (aka PSL) on Sept. 3, but in celebration of the popular drink's 10-year anniversary offered fans a secret code on Aug. 28 to "unlock" their local store and make it available to everyone early. That same day, Einstein Bros. Bagels and Noah's New York Bagels launched their pumpkin menu, with new items including pull-apart pumpkin bagel clusters and a frozen pumpkin pie latte. Some pumpkin craft beers were available even earlier, in mid-August.
Companies say the trend is less about a domino effect of early holiday items pushing fall ones even earlier, as it is meeting the rising consumer demand for pumpkin. Glenn Lunde, chief concept officer for Einstein Noah Restaurant Group, said the brand's launch was about a week earlier than last year, but still timed to Labor Day. "Customers look forward to fall, and part of the fall these years is pumpkin season," he said.
"This is a time all its own: Winter, spring, summer and pumpkin spice latte season," said a Starbucks spokeswoman, noting that fans talk about the drink year round, with social media anticipation starting to build as early as June. "It's a testament to the pumpkin frenzy."
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"I hold my breath until it is autumn," said Pat Manning. The 74-year-old retiree first had a Starbucks PSL seven years ago, and aims to get a daily fix every year during the drink's short window of availability. (That's true even when fall temperatures top 70 degrees, as is often the case in Las Vegas, where she lives.) "You have to squeeze in as many as you can," she said.
Reactions like hers that have companies scrambling to put pumpkin flavors on their menus. Restaurants' pumpkin-inspired limited-time offers are up 234 percent from 2008 to 2012, while overall limited-time menu offers have grown 143 percent over the same period, according to Datassential Menu Trends. Although it's early, menu mentions of pumpkin for 2013 are already up 6 percent compared with last year.
Pumpkin is particularly effective for marketing because it has scent appeal as well as taste, said Aaron Allen, an independent restaurant consultant. "It's a smell you don't forget," he said. Making it a limited-time offer adds to the appeal. "It's a promotional strategy tapping into the human psyche on avoiding scarcity," he said. Avid fans (like Manning) are likely to increase the frequency of their visits, buying more than they might if the item were available year-round.
But that seasonal nature means it's unclear just how much companies can capitalize on pumpkin fans, said Maeve Webster, senior director for Datassential. "If this is only going to be appropriate in one or two seasons, how relevant is that going to be?" she said.
Pushing the introduction of pumpkin foods earlier does have some risk of backlash from people angry that fall is invading summer. More often, though, it's good publicity to drive consumers to buy during that peak fall period, Allen said.
Sales don't tend to really pick up until closer to October, when chillier weather sets in, said Scott Bernhardt, president of Planalytics, a research firm that analyzes the impact of weather on sales.
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Morning temperatures can drive sales even earlier in the Northeast (which, reports Datassential, has the most pumpkin menu penetration). "How cold is it when the kids are going to the bus stop?" Bernhardt said. "That drives the morning routine, and whether you go for that second cup of coffee."
Not that the warm weather is much of a deterrent. Both Dunkin' Donuts and Einstein Noah introduced frozen pumpkin drinks this year, and Starbucks' PSL can be made iced or as a Frappuccino.
—By CNBC's Kelli B. Grant. Follow her on Twitter