As summer said its unofficial goodbye at the close of Labor Day, the fall leaves were gearing up for the biggest show of the year.

The summer season remains crucial for the state’s $7.7 billion annual tourism industry, but the leaf-peeping season has become the biggest money-maker for hotels and restaurants.

“It’s the biggest change we’ve seen in 20 years — Columbus Day weekend is the biggest holiday of the year,” said Dick Grotton, president and chief executive of the Maine Restaurant Association. “A lot of retirees wait for the summer crowds to leave and vacation in the fall. We’ll have hundreds of bus tours bringing in business. It’s really very, very huge for us.”

The leaf-peeping bus tours create a “mob scene” for stores in the Old Port, such as Shipwreck & Cargo on Commercial Street, said owner Brewster Harding. But once mid-October passes, sales for the year fall off.

“We have to make our money from mid-May to mid-October. The season’s pretty much over by October 20,” Harding said.

Businesses should be happy with this year’s leaf display. Mother Nature has been cooperating, setting up Maine for the best leaf peeping in years after several seasons of mediocre color displays because of poor weather conditions, said Gale Ross, Maine foliage spokeswoman.

“We should have a better-than-average foliage season. It will be the first year in quite some time we’ve had nearly normal conditions,” Ross said. “The warm days and cool nights will help the leaves along over the next few weeks.”

The first color showcase should peak in northern Maine toward the last week in September, followed by western, southern and central regions during the week of the Columbus Day weekend and into the next week. The coast of Maine is the last region to peak, Ross said.

“Once we start getting toward peak conditions, we don’t want any tropical storms,” Ross said. “Last year, Hurricane Irene blew the leaves off trees and really dampened the leaf-peeper season.”

The fall also marks the busiest time for cruise ships along the coast. A total of 38 ships with a capacity of more than 20,000 passengers will enter Portland in September and October, according to the Port of Portland. Cruise passengers tend to be big spenders on souvenirs and Maine-made products, but are less likely to eat in local restaurants because they have meals on the boat, local business owners said.

“Now through the holidays is when we’re the busiest. Fall is stronger than Christmas, actually,” said Steve Anderson, manager of Edgecomb Potters Gallery on Exchange Street. “This is our profit margin for the year — these few months.”

Anderson said that although cruise ships do bring in spenders, the store tends to do best with Amtrak travelers who come for the day from Boston. The day-trippers come to spend and they visit throughout the year, rather just in the peak tourist season, he said.

A vibrant fall foliage season follows great summer conditions for travelers and locals alike. Maine had early warm temperatures in the spring and a normal to slightly warmer-than-normal summer, said Chris LeGrow, a meteorologist with the National Weather Service. That compared favorably with the scorching temperatures that stifled Boston, New York and Philadelphia and sent tourists heading north for the more temperate climate.

“You can’t minimize the fact that weather was in our favor this year. It was nice here and very hot in the metro areas that feed us,” said Greg Dugal, executive director of the Maine Innkeepers Association.

From May through the end of July, traffic at the York toll plaza was up 1.3 percent over last year, said Charles Colgan, professor of public policy and management at the Muskie School of Public Service at the University of Southern Maine. “Both May and June were up, but July was soft,” Colgan said.

Online requests for Maine visitor guidebooks rose 16 percent this year, said Carolann Ouellette, director of the Maine Office of Tourism. The state also launched an advertising campaign on the Red Sox Radio Network, which allowed it to change the content to highlight different fairs, festivals and special events throughout the season. The tourism board also did advertisements in suburban train lines such as Long Island Rail Road, New Jersey Transit and Connecticut to tap the New York metro market, which is the second-biggest pool of visitors after Massachusetts.

More than 80 percent of Maine tourists are repeat visitors, so once the state lures someone, they have a loyal fan, Ouellette said.

In May, lodging and restaurant sales each rose about 7 percent over last year. In June, restaurant sales rose 7.6 percent and lodging surged 14.7 percent, according to the State Planning Office. Sales data for July were not yet available, so restaurants and hotels only had anecdotal evidence that sales may have been soft because the Fourth of July fell on a Wednesday.

“A midweek July 4th is the worst,” Dugal said. “People don’t know what weekend to take off and Wednesday bookings are OK, but that’s only one night.”

Acadia National Park saw a 17.6 percent jump in visits in May, and a nearly 4 percent jump in June. July, however, softened, with visits down 3.6 percent, the park said. Data for August was not yet available.

The first two weeks of August are typically the strongest of the summer tourism season. Overall, this August as a whole is expected to eclipse last year because of the general upswing in tourism in the state and favorable comparisons with last year, when Hurricane Irene dampened the end of August and curtailed many vacations.

Retailers and restaurants in Freeport reported flat-to-better sales for the season because of an influx of Canadian shoppers and new restaurant openings, said Janet Dutson, executive director of FreeportUSA, which represents the town’s merchants. The nice weather may have kept some tourists outdoors instead of inside shopping, Dutson said.

Funtown Splashtown USA in Saco benefited from the expansion of its water park and a tweak in its advertising to target more of the Boston market, said Ed Hodgdon, head of marketing for the amusement center. He wouldn’t disclose ticket sales, but said the business had seen an increase in tourists from Canada and southern New England during its peak season from July 15 to Aug. 15.

Funtown Splashtown typically closes on Labor Day, but this year it will hold a bonus day on Sept. 9 with discounted pricing.

“The summer tourism season has been reasonably improved over last year,” said Colgan, of USM. “July Fourth kind of messed things up a bit, but overall, there’s modest improvement this year.”

Staff Writer Jessica Hall can be contacted at 791-6316 or at: [email protected]