Even before the Behnke Nurseries closed up shop in Beltsville last weekend after 89 years, the impending end of this cherished Washington-area institution was apparent to any one who visited in recent weeks.

Lots where dozens of container trees and shrubs would normally stand were thinning to reveal fields of asphalt, and the benches that were until recently jammed with one-gallon containers of perennials and grasses were bare, too.

Within the enclosed and labyrinthine nursery shop — there were always so many unpredictable passages and chambers at Behnke’s — office fixtures were up for grabs where glazed pots once crowded. As you made your way toward the checkout registers, Christmas goods were heavily discounted. The racks were well picked over when I visited recently, but there was still an authentic, antique sleigh. Supply your own red-nosed reindeer. Once at the heart of Behnke’s festive displays, the sleigh now stood a little frayed and forlorn, and its isolation seemed to capture the sadness and loss of the nursery’s closure.

Behnke’s began as a simple roadside plant stand run by two German emigres, Albert and Rose Behnke, in the 1930s, when the D.C. suburbs were only just getting started. Workers in an expanding federal government were moving into their new neighborhoods of red-brick Cape Cods. Behnke’s thrived by furnishing all those new yards. By the time some of the founders’ children began to take the reins, Behnke’s was so popular that it employed traffic cops to direct weekend customers in and out of the 12-acre site off Route 1. At its height, the enterprise included large off-site plant production greenhouses, first in Largo and later in Lothian, Md.

The main retail location, created initially as a place also to propagate and grow plants, morphed into a disparate horticultural wonderland, its haphazardness contributing to its quirky appeal.

For staff and customers, the past few weeks have offered a moment to reflect on the qualities that made Behnke’s special. It was a place for inter-generational family outings and their attendant memories, a place to find reliable advice, and a place where both beginner and advanced home gardeners could find what they needed.

Professional horticulturists found a home there, some for a year or two, others spending their entire careers at Behnke’s, where they developed a rapport and friendship with regular customers.

In the customers’ memories book, a writer named BT seemed to sum up the last, sad days of Behnke’s: “Where am I going to go? Who am I going to see? What am I going to do?”

The family business closed for a number of prosaic reasons: The next generation was not gung-ho on the nursery business, key employees were reaching retirement age, the structures and their systems were aging and in need of a major overhaul, and the land became too valuable for its current use. “It would cost millions of dollars to fix this up,” said Stephanie Fleming, vice president and granddaughter of the founders. The family is preparing to develop the property.

It would be a mistake, thus, to ascribe Behnke’s closing to an industry-wide malaise, but the same forces the company faced are at play in independent garden centers everywhere. It’s a retail business that is inherently precarious and faces challenges unlike any other. Many went under in the Great Recession, and the survivors have had to navigate a retail landscape that shifted fundamentally when mass merchandisers got into the business. More recently, e-commerce has added further competition.

Independent garden centers can’t compete on price and instead play to their strengths: plant selection and quality and expert growing advice. Still, it’s a tough business.

The most obvious challenge is that the merchandise is alive and needs to look good to sell — that means employing enough knowledgeable people to nurture it seven days a week.

The other market phenomenon is that most of the year’s takings occur in a 12-week period from mid-March to early June. Spring is the season most people shop for plants, for obvious practical reasons, but for emotional ones, too; nothing is more affirming after a long, dead winter than filling a pot with pansies or refreshing the herb garden.

“The rest of the year, except for a week or two at Christmas or in the fall, we are basically losing money,” said Alfred Millard, Behnke’s president. (He started work at the nursery as a 13-year-old, 57 years ago.)

But spring weather is unpredictable, and the rain-soaked weekends that seem to have become the norm can put a serious dent in sales.

“If it rains on Mother’s Day,” Fleming said, “it’s awful.”

Another dynamic that may not be obvious: Retail nurseries used to grow much of their own stock; at one point Behnke’s horticulturists were raising 200,000 perennials a year. But garden centers today source plants from a network of growers, some larger than others.

Jonathan Pedersen, vice president of sales and business development for the nation’s largest wholesale grower, Monrovia, says his company supplies about 2,500 independent garden centers in North America. The number has shrunk by about 500 in recent years, but “the top 1,000 have gotten larger.”

In addition to Monrovia, garden centers rely on a network of growers that also tend to be family-owned businesses, and though corporations have tried to consolidate the industry, “it hasn’t worked very well,” Pedersen said. “With seasonality, the weather, it’s very difficult for outside, very smart people to understand our industry. It’s complicated.” The company, based in Azusa, Calif., also supplies its annuals, perennials and, especially, its woody plants to Lowe’s stores and to a vast but little-known industry segment called re-wholesalers, which supply landscape contractors.

I asked Pedersen whether he saw a rosy future for independent garden centers. “It’s a good future; rosy maybe too optimistic. They have to work hard. It isn’t easy,” he said. “I still see a good solid future for a strong individual able to offer a niche with product offerings and customer service. The business is there.”

Behnke’s departure underscores a few important points. In greater Washington, urban land values — and rents — are at such a level that it is unlikely another full-service nursery will erupt somewhere inside the Capital Beltway. After decades in Tenleytown, Johnson’s Florist and Garden Centers last year retreated to its two suburban Maryland locations in a rent disagreement with its landlord, American University. Small boutique garden centers might fill the void, especially with the millennial craze for house plants, succulents and tropicals.

Some people may wonder why we even need bricks-and-mortar garden centers anymore.

Buying plants online may seem the obvious alternative today, but how does a customer know whether something will grow here? Google it? A shrub that will grow in Washington may not thrive up the road in Baltimore, and vice versa. I’d want to bend the ear of someone who has grown and evaluated a variety where I live.

And preferably, I’d like to observe a plant before I buy it. I want to see the branch structure, I want to see whether rabbits have been feasting on it, and whether it has a root that has wrapped itself around the lower trunk, portending self-strangulation. Is the bark on that stewartia tree prettier than on the next?

We need good garden centers, filled with regionally appropriate and high-performing plants and knowledgeable staff.

For the customers of remaining retail nurseries, I offer some advice: Don’t shop in springtime alone. Unless we are in a drought or the ground is frozen, virtually any time is a good time to put in hardy plants. Late summer through mid-fall is an optimal period to plant trees, shrubs and perennials when they can turn to growing roots rather than leaves and be established by the following year.

Don’t buy plants because they are in bloom; buy them because they are right for the space you have allotted them. And don’t be a fair-weather consumer. Shop in the rain; it’s so liberating.

At a time of growing concern about climate change and the loss of habitat and biodiversity, the garden center offers some tangible way to explore and aid the plant world. “We are the original green industry,” said Danny Summers, managing director of an industry consultancy, the Garden Center Group. “We don’t really sing our song strongly enough.”

The chorus just lost an abiding voice in Behnke’s, but the hymn continues.

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