In 2016, Congress failed to renew a provision of immigration law and so significantly reduced the number of foreign temporary workers who are granted H-2B visas. (Nick Cote/For The Washington Post)

For three days each January, landscapers stroll the aisles of the Baltimore Convention Center, kicking the tires of ride-on mowers, ordering trees for the spring planting season, and generally looking for suppliers who can help them trim costs and increase business in the season ahead.

This year, they were drawn to a new exhibitor at the Mid-Atlantic Nursery Trade Show. A lawyer named Kara Youngblood spent the hours fielding questions from a raft of green-industry employers grappling with a crisis at least as worrying as the economic downturn a decade ago.

"The landscape companies I have met here are livid," she said. The object of their anger? Uncle Sam.

In 2016, Congress failed to renew a provision of immigration law and so significantly reduced the number of foreign temporary workers who are granted H-2B visas. Previously, workers who had earlier received a visa, which allows them to work up to 10 months per year in the United States, could return to their employers without coming under the annual limit. Youngblood said the action — or inaction — effectively reduced the number of H-2B workers from about 350,000 to the annual cap of 66,000. It is from this smaller pool that landscapers must compete with all other industry sectors for foreign workers. Half of them are admitted from October to March, further reducing the availability of workers when landscapers need them.

"What's happening now, you're that landscape guy bringing over a foreman for 10 years and you weren't worried about him getting that visa — now that just didn't happen," she said. "It's a gamble."

Foreign workers employed by nurseries and production greenhouses are considered agricultural employees and are admitted under the related H-2A visa program. There is no cap on those visas, but nursery growers say labor shortages among landscape contractors will harm growth across the industry.

Immigration attorney Kara Youngblood, a new exhibitor at last week’s Mid-Atlantic Nursery Trade Show in Baltimore, answered questions about the worker shortage facing the landscaping industry. (Adrian Higgins/TWP)

Under both programs, employers must show they first tried to recruit American workers. The common refrain from the landscape industry is that the demand for labor outstrips the supply — people generally don't want to work in physically demanding jobs outside in the elements.

"It's cheaper to hire somebody down the street" than a foreigner, Youngblood said. "If that were an option, they would." She is based in McMinnville in central Tennessee, a major region for ornamental-plant production in the United States.

The lower numbers, of course, do not convey the human stories, the bonds between family-owned businesses and their returning workers, most of whom come from Mexico and Central America.

President Trump has made immigrants a target from his populist platform, although Youngblood said the Obama administration "very quietly" waged a concerted campaign of deportation of undocumented immigrants. The current risk of mass deportations of immigrants under temporary protected status and DACA programs is likely to compound the problems facing landscapers, said Youngblood, whose firm has opened an office in Tysons Corner for lobbying purposes.

At the trade show last week, Youngblood's booth was sandwiched between a woody-plant grower and a manufacturer of plastic seed trays. Surveying the showgoers, she said, "I'm pretty sure most here aren't going to get [enough] workers and don't know what they are going to do," she said.

She may have been speaking of Andreas Grothe, who runs New World Gardens, a small landscape company in Parkton, Md., that builds and maintains gardens. He said he paid an agency $9,000 to process three H-2B workers who were supposed to start March 1, but they didn't get their visas, and he must now pay an additional $1,200 to see whether he can get them for April 1.

"These are people who worked for me in the past," he said. Due to similar problems last year, his business dropped by a third. "I had to call customers and apologize that I couldn't do that job anymore because I couldn't put people on the job."

The rub is that many landscapers report booming business as the economy has rebounded and their customers are cashing in on gains in the stock market. "I have plenty of jobs and business is wonderful," Grothe said. "But the reality is that I have right now two employees, and I should have eight."

Lancaster Farms in Suffolk, Va., is a large-scale grower of container-grown trees, shrubs, perennials and annuals at three locations. In peak growing seasons, Art Parkerson employs 120 people, a third of them H-2A workers.

"We can find [American] field workers, but they don't want to stay field workers," desiring instead to move into sales or other more comfortable jobs in the company, he said.

About 70 percent of his stock goes to landscape contractors, the rest to independent retailers. "A lot of our customers would grow their business significantly if they had access to labor," he said.

Directly across the trade-show aisle from Youngblood, Daniel McMahon had every expectation of a banner year. He works for a division of Ball Seed Co. that provides transplanting equipment for greenhouse growers. Standing by an automated soil-potting machine, he removed a half-inch-square plug containing a pansy seedling — one of 400 in the flat — and placed it in a retail-size tray. This single step, where growers take purchased seedlings to grow on to consumer size, is the most profitable in the nursery trade, he said.

He handed me a couple of brochures for transplanting machines. One is manually operated, costs $5,000, and allows three people to do the work of 15. The second flier was for the TTA PackPlanter, a robotic transplanter that costs $150,000 and does the work of 25 to 30 people, he said. "All the equipment companies are having the best year," he said.

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