Linda Hipp did not start a golf apparel company in 1997 because there was no golfwear on the market. She started Lija because none of it was attractive—at least, not to a thirtysomething, style-conscious woman.

Another golfwear entrepreneur, Kate Sutton, who founded her line, Birdie, in 2005, describes the boxy, conservative pieces that frustrated her: shorts with frumpy pleats, khakis that rode too high, oversize polo shirts in stiff piqué fabrics with masculine stripes.

“I felt uncomfortable in what I was wearing when I was playing golf,” Sutton says. “With a group of guy friends, I would look down at what I was wearing and what they were wearing, and there was no difference. It was as if they took men’s golfwear and shrunk it to women’s sizes.”

Independent golfwear companies such as Lija, Birdie, and Verdina—which was launched in New York last year—have found that they can make major green on the greens by creating modern looks for the burgeoning number of female golfers. (View slideshow.) San Francisco’s Birdie sold $700,000, wholesale, in its first fiscal year. Verdina’s sales have already tripled since its founding. And Lija, the best-established of the bunch, has seen revenue grow at a rate of 40 to 50 percent per year since 2000.

Lija, Birdie, and Verdina have succeeded by making fashion-forward golfing clothes that appeal to women on and off the course. Lija’s low-slung shorts with windowpane checks playfully riff on traditional plaid golfing pants, while a voile dress with daisy-shaped buttons could work on the beach. Birdie targets its colorful golf gear at the “younger hot soccer mom” (think stretch cotton skirts in sorbet colors and fitted polos with big, white collars). Verdina’s clothes are designed by Nicole Elizabeth, a veteran of Nautica, Ralph Lauren, Halston, and Tahari. For Verdina, fit is everything: A pair of white pants made from a blend of cotton, linen, and lyocell (a fiber derived from wood pulp), with neat pin tucks in the front and back, sums up the design aesthetic.

“Our customers should be able to wear the clothing throughout their day, with the only necessary adjustment being a change of shoes,” says Dana Coppolino, Verdina’s president and one of its three founders.

All three companies are using their success in golf as a teeing-off point. Aiming to become more than golfwear makers, they’re expanding on the same crossover appeal they brought to golf apparel, diversifying their lines to attract customers who are looking for clothing to wear on ski slopes, at oceanside resorts, or on city streets.

“Golf for women is a very interesting business,” says Marshal Cohen, chief industry analyst at NPD Group, a market research firm in Port Washington, New York, that pegs women’s-golf-apparel sales at $1.7 billion per year. Cohen believes there is still enormous opportunity, especially in golfwear-inspired streetwear. “The impulse for women to buy golf apparel is very low, but bring it to the street and they jump all over it,” he says.

Birdie now sells such accessories as key chains, hats, and a leather weekend bag that has a separate compartment for muddy golf shoes. Customers can use the bag for non-golf activities too, stashing everything from diapers to wet bathing suits in the compartment, and Birdie’s Kate Sutton sees this as evidence of the broad appeal of the designs, which are sold in upscale clubs, resorts, and even Isetan, a major Japanese department store.

Verdina has launched a mini-line of clothing for the resort or spa, featuring pants and skirts made of French terry cloth. And Lija, which founder Linda Hipp calls a lifestyle brand—with clothes suitable for working, jogging, hiking, or playing tennis—plans to introduce its own outerwear line, to be sold in ski resorts. It will include such pieces as a puffy vest with fur trim. But whether you’d want to wear that on the links ... well, let’s just call it a long shot.