Recent mild winters have encouraged Washington area gardeners such as Peter Schenk to push the horticultural envelope with plants that really shouldn’t grow here. This winter, they didn’t.

“Dead as a doornail,” said Schenk, recalling his examination of a trendy variety of the mahonia shrub named Soft Caress. He gave it his own soft caress only to find that “the entire bark and cambium layer just sloughed off, black in my fingers,” said Schenk, a professional gardener based in Alexandria.

Spring arrives in theory this week, but for most people, a long and bitter winter has clung to our yards and to our psyches, capping the gloom with a heavy wet snow that came out of the blue at the start of the work week.

Schenk and other horticulturists may be itching to dig the soil, but they are also expecting to see widespread winter damage in the coming weeks as fresh growth contrasts with branches and whole plants that have succumbed to winter freeze.

If the severity of the winter becomes a new norm, “all kinds of rethinking will be happening as to what will grow and what won’t,” said Schenk. “It’s a little scary.”

Gardeners report early signs of winter kill to such popular landscape plants as hydrangeas, boxwood and herbs considered safe in recent decades — rosemary and sweetbay.

For another Alexandria gardener, Audrey Faden, a years-long mission to cultivate marginally hardy plants may have come to a halt. She worries about a eucalyptus tree that had grown to 20 feet, subtropical perennial sages, agastaches and other plants she tends at a series of public demonstration gardens at the city’s Simpson Park.

Camellias, with their handsome glossy leaves and cool loving blossoms, have taken it on the chin. March and April flowering Japanese camellias won’t have much of a show this year, said Leslie Zupan, president of the Camellia Society of the Potomac Valley. Generally, buds have been destroyed by freezes, though the shrubs themselves are alive. But the more tender fall blooming types, known as sasanquas, have taken a bigger hit, with widespread branch dieback and death. “I have a beautiful espaliered (variety) Kanjiro, and I think it’s totally dead,” she said. Society members will know in about a week, she said, if they have enough blooms between them to stage their annual show, scheduled for April 12 at the Potomac Community Center.

William McLaughlin, plant curator at the U.S. Botanic Garden, said some hardy, spring-flowering trees “look like they are in this eternal holding pattern.” Marginal plants that he has been growing – gardenias, palmetto palms, yuccas and agaves – have perished.

The season is about three weeks behind. At Dumbarton Oaks, the ornamental plums should be showing pink buds by now but are still firmly closed, said Gail Griffin, director of garden and grounds. Tour buses are wandering around the budding but flowerless Tidal Basin like hungry ruminants.

The absence of other spring heralds such as daffodils, saucer and star magnolias and flowering quince has delayed the whole edge-of-spring thrill, but the dearth of blooms isn’t necessarily a bad thing.

The lingering has reduced the risk of blossoms opening and then getting frozen. Griffin recalls how in 1998 a magnolia bloomed on March 10. “It was hit by a freeze that night,” she said. “It’s tightly in bud now.”

For Jeff Lundberg, who services and repairs lawnmowers from his shop in Vienna, the tenacious winter has created different headaches.

In a normal winter, homeowners would start to bring in their mowers in December and January, but instead folks arrived with snowblowers and generators that needed urgent repairs. In a normal late March, he would have a two-week backlog of mowers. This year, it’s four weeks — an amount normally seen in late April “when people who go out to mow for the first time find their mower won’t start,” said Lundberg, owner of Vienna Lawnmower Sales and Service.

If there is a silver lining to the delay and damage, it’s that April will bring strange and beautiful confluences of blossoming as March flowers finally open alongside later blooms. The magnolias may well be around with the cherry blossoms, which will flower with the crab apples and the wisterias and the lilacs.

Hang on to your hats, Schenk said, because “everything is going to go, pow.’