A corner lot in the Glynn Tarra subdivision a few miles north of Leesburg is home to plants from many states. The new garden beds are crowded with day lilies from Suffolk, Va., "Knock Out" roses and wisteria from Georgia, Yoshino cherry trees and Sioux crape myrtle bushes from North Carolina, and a Fat Albert spruce all the way from Portland, Ore.

Although Loudoun County's roots are primarily agricultural, none of the new greenery -- which was planted by Meadows Farms, a Loudoun-based landscaping company -- is locally grown.

As farmers look for ways to stay in business despite rising property taxes, they needn't look much further than the thousands of new homes cropping up each year, each requiring a lawn, shrubs, garden beds full of flowers and trees, said Lou Nichols, Loudoun's agricultural development officer.

"I think the nursery business has the potential to become one of the most profitable things that people can do out here," Nichols said.

Tree farms and greenhouses that grow annuals and perennials are high-return, land-efficient operations that can bring in several thousand dollars an acre, compared with hundreds of dollars an acre from such traditional commodities as grain and cattle, Nichols said.

But so far, even with customers willing to pay $10,000 to $20,000 for landscaping, it seems that few farmers have begun growing anything for their new neighbors' new yards. The county's rural economic development office's Web site lists fewer than 12 farmers who grow annuals, perennials or shade trees for sale.

One reason for the slow adaptation to the nursery market could be because many landscape contractors are willing to travel across the state and the country to find cheaper plants. One significant exception is sod, which has a two-day shelf life and must be purchased locally.

"You do like to support the people close to home as much as possible, but on the other hand, you have to buy the best product for the best price," said Dave Reed, vice president of Chantilly-based Meadows Farms, which has 20 nurseries in the Washington area and a landscaping division that sends out 65 crews a day. "We're large enough; we can bring in truckloads from pretty much everywhere," he said.

Nichols said Loudoun farmers can't compete in volume and price but can offer more exotic plants or bigger trees, which are more expensive and unwieldy to transport but can appeal to newcomers who don't want to wait years for a four-foot cherry tree to provide shade.

Another advantage to buying locally is that trees and shrubs grown in the same soil and under the same weather conditions can survive better in their new yards, said David Lohmann, manager of Abernethy & Spencer Greenhouses nursery in Purcellville, which has a large selection of native plants and trees.

For some homeowners and for contractors who aren't landscaping entire shopping centers or subdivisions, such considerations can be important.

"There's two markets," said Winston Porter, who runs a 10-acre wholesale tree nursery with his wife, Linda, in the back yard of their Paeonian Springs home.

There are retail nurseries or contractors that look for the lowest price for plants and trees to landscape shopping centers or subdivisions, but there also are many landscapers who work on smaller jobs and are more likely to buy trees locally, Porter said.

Warren Robst, who owns Locust Landscaping Co. in Leesburg, has a smaller company, with only 13 employees, and he tailors his shopping to each job. For bigger projects, he said he'll look farther for quality products at lower prices. For smaller jobs, however, he'll often buy from local wholesalers or re-wholesalers, who purchase plants elsewhere and sell them locally.

For locally grown trees, Robst said he will sometimes go to Tarara Nursery in Leesburg, which has more than 100 acres of such trees as river birches and Japanese maples. For flowers and plants, there are few local nurseries where he can shop.

Greenhouse farming requires a lot of handwork and precision. This shift can be difficult for many Loudoun farmers, who grow are used to growing in fields and use machinery, said Gary Hornbaker, the county's rural resources coordinator. Many farmers would rather move out of the area than switch to a totally different kind of farming, he said.

But Nichols said that for farmers willing to adapt, the transition can be financially rewarding.

"Greenhouses are where the money really is, on an acre-for-acre basis," he said, because plants are grown in high density, crammed onto tables and hanging in baskets.

Layng's Flower Farm moved to Aldie from Fairfax County three years ago. With 16 greenhouses and 60,000 square feet "under plastic," the nursery doubled or tripled the greenhouse space Loudoun has in production, Nichols said.

The family-run nursery grows plants and sells them wholesale to garden centers, hardware stores, landscapers and churches, said Melissa Layng-Lottchea, whose father started the business in 1979. The family hopes to increase its retail market, which now accounts for 10 percent of the business.

Other greenhouse nurseries market exclusively to the growing number of residents who want to fill their new gardens.

Ellmore's Garden Center in Hamilton grows annuals, perennials, vegetables and herbs on a five-acre farm that includes a half-acre of greenhouse space.

"We're not like the stuff you see in the big-box stores. We strive for a little niche, a little quality, said Harry Ellmore, co-owner of the nursery. "We try to make sure everything is alive."

Ellmore said he and his wife, Barbara, also offer advice on where to put plants and how to water them to residents starting flowerbeds or vegetable gardens for the first time, he said. Their sales increased 70 percent last year, he said.

Nichols himself has started a retail tree-growing business. In addition to Christmas trees, he has planted several thousand shade and ornamental trees, such as gingkos, flowering cherry and Japanese snowbells, outside his Purcellville home. He is growing the trees in containers and marketing them to people who want to plant them in their yards.

He said he is counting on the growing suburban population to support his latest venture and thinks other farmers should follow his lead.

"There's room for more," he said.

Winston Porter runs a 10-acre wholesale tree nursery with his wife in the back yard of their Paeonian Springs home.Rows of maples at Porter Tree Nursery, which sells to retail nurseries, contractors and smaller landscapers.