Think of Buffalo. What immediately comes to mind?

Shopping malls, probably. And cheap flights from the airport there. And during the winter, awesome amounts of snow.

But get this: Buffalo also has the distinction of holding the most popular celebration of gardening in North America.

Called Garden Walk and staged every summer, it was dreamed up by two enthusiastic amateur gardeners over two decades ago. However, what’s happened since then is truly remarkable. The event has kept on getting bigger, like a pumpkin on steroids, and wound up becoming a huge tourist attraction. Last year, for instance, some 50,000 people came, from as far afield as California.

In fact, good luck finding a room in the Buffalo area on the last weekend in July, when Garden Walk always takes place. Many hotels are sold out months in advance.

But even if you have to settle for accommodation on our side of the border — or simply drive down for the day — make the effort to experience Garden Walk this summer. It’s unique and in a class by itself. Here’s why:

First, the tour is totally free, with no “snob” credentials. There’s no need to buy advance tickets or wear a wristband. You can even take the dog along. This kind of openness was insisted upon, right from the start, by the couple who got the ball rolling back in 1995, a history professor named Marvin Lunenfeld and his partner, Gail McCarthy.

“From the beginning, I wanted no prizes for the best garden and no admission fees,” explained Lunenfeld, in a recent book about Garden Walk. “I didn’t like the idea of elitism or exclusivity. It was to be about community, not competition.”

He got his wish. The tour has gradually spread from a handful of gardens around Lunenfeld’s own home to encompass many neighbourhoods in downtown Buffalo. This summer no fewer than 400 front and backyards will be open the public — a staggering number, when you consider that organizers of most garden tours are happy if 20 homeowners agree to take part.

The impressive architecture in the city core is a revelation too. Unlike downtown Detroit (now too decrepit and dangerous to venture into) Buffalo’s old residential streets are a delight. They’re lined with Victorian homes that are mostly in very good repair, with lovely front porches and lots of gingerbread trim. I felt quite safe, strolling around them last year.

In fact, the relaxed feel is the best part of Garden Walk. There’s no pressure to “hurry around and see everything” at this people-friendly gathering. Instead, you simply pick up a map at tour headquarters, then wander down any street, detouring into interesting gardens that display a yellow and green flag. Some are certainly big and swanky, with professional landscaping. But far more are modest little spaces with neat gardening ideas that anyone can copy. The gardeners, who may be homeowners or renters, are usually around to chat with, and there are plenty of neighbourhood cafes to flop into for an ice cream cone.

I could go on, but see for yourself. This year, Garden Walk runs on Saturday, July 30, and Sunday, July 31. Gardens are open from 10 a.m. to 4 p.m. Wear cool clothing, a hat and comfy shoes. The temperature in Buffalo can soar at this time of year. Tour maps are available at several locations. For more information, see their excellent website: gardenwalkbuffalo.com.