Hearty blooms brighten cool days

Early-blooming, cold-hardy pansies and violas are among the first flowers to add a welcome blast of color. (Darrell Gulin)

Crocuses have just pushed their heads above ground, and daffodils and tulips aren't far behind. But after a long winter and the dull browns of early spring, New Englanders are eager for more.

Summery flowers like petunias and geraniums are no match for the chill of early spring. But intrepid gardeners know that some colorful offerings can handle the chilly weather - even a surprise dusting of April snow.

Two of the most familiar cool-weather flowers are pansies and their smaller cousins, violas. They come in a range of flower sizes and colors - from pure white to blackish purple and colors in between. The petite pastels are ideal for this time of year, especially when planted in a mix with other cold-weather survivors.

The potted primrose can also handle cool spring temperatures. But first it needs to adjust to the sudden temperature change. Put your primrose outside for an hour or two on a sunny day, and increase its time outdoors over the next five to six days. By then, it should be acclimated to its new outdoor home.

Other cool-weather spring flowers include English daisy, creeping speedwell, forget-me-not, wallflower, columbine, and alyssum. Many can tolerate a light frost and temperatures down to about 28 degrees Fahrenheit. Pot marigold, twinspur, pinks, verbena, nemesia, linaria, and snapdragon prefer slightly higher temperatures, but do extraordinarily well in cool weather, too.

Jim Putnam of Pleasant View Gardens in Loudon, N.H., says many of these hardy plants can handle early spring temperatures below 28 degrees Fahrenheit. "If the temperature goes below 28 degrees Fahrenheit, they can suffer some damage, but they'll come back," Putnam says.

Mark Cutler, greenhouse manager for Mahoney's Brighton location, says warmer spring temperatures are arriving later this year than last. Within the next two weeks, he says, temperatures should gradually warm to the point where cool spring plants will be available in garden centers. If chilly days persist, Cutler recommends putting the plants outside on sunny days and bringing them into a garage or a cool, enclosed space at night. Once daytime temperatures are consistently in the 50-degree Fahrenheit range, the plants can spend all day outside. But they should still be protected during chilly nights.

Putnam advises looking for plants that have a compact shape and dark-green leaves, indicating they were raised in cool temperatures and will be ready to live outdoors. Soft, lush plants, Putnam says, have spent time in warmer temperatures and will need to acclimate to cooler conditions over a five- to six-day period. When in doubt, ask the retailer what conditions are most appropriate for the plants you're purchasing.

Other tips?

"It would be very easy for someone to water them too much," Putnam says. "It's so cool outside and the plants aren't as vigorous as a big petunia." And a dose or two of all-purpose fertilizer during the spring should be just fine, he says.

Many cool-weather plants will fade once summer comes. But with a little maintenance, they can survive for a second season of flowers in fall. Cutler says pansies can survive through summer if planted in a tree's dappled shade. Others, such as verbena and nemesia, will be do well all through summer. Give them a good trim and remove their seed heads, he says, and they'll continue to bloom right through the chilly days of fall.