The term "Northeast" sometimes stretches elastically to include Canada and Virginia, while many consider the region confined to New York, New Jersey and the New England states. Whatever the definition, gardeners looking for flowering plants suited to the Northeast's chilly nights, shorter growing seasons and rainy springs and autumns will discover literally hundreds of options.
So many flowers grace Northeastern gardens and meadows that choosing among them presents a bigger problem than finding enough cold-hardy varieties. Yarrow, columbine, bellflower, delphinium, lupines, peonies, foxglove, and poppies work well in formal or cottage gardens. For romantic, historical plants, consider Queen of The Prairie, lady's smock, love-in-a-mist, Cupid's dart, kiss-me-over-the-garden-gate and love-lies-bleeding.
While the distinction between perennial flowers and flowering herbs sometimes blurs, certainly many annual and perennial herbs bloom beautifully enough to be counted as cold-hardy ornamentals. This by no means complete list includes bee balm, catnip, lady's mantle, mint, chives, and lady's mantle, which have the additional virtue of tolerating shade. Sun-loving chamomile, dianthus, lavender and borage also rub happily rub elbows with other herbs or flowers.
By their very definition, annuals don't have to be hardy enough to survive Northern winters. Still, some adapt better to our chilly nights and shorter summers than more tropical annuals. Among the region's favorite annuals for sunny gardens are marigolds, sunflowers and zinnias, Shade-lovers include impatiens, begonias and caladium. Some annuals, such as autumnal chrysanthemums, over-winter or self-seed, making for a happy surprise the following season.
Many groundcovers suitable for New England and neighboring regions are shade tolerant, bringing splashes of color to dimly regions. Several groundcovers flower through spring or summer---sometimes both--before offering up bronze or red foliage in the fall. Purple and blue-flowering groundcovers include bugleweed, hosta and vinca. Pale pink or white blooms appear on Lily of the Valley, bearberry, cotoneaster, epimedium, candytuft and phlox. More vivid splashes of reds and magentas come with dwarf azaleas and bigfoot cranesbill.
Trees and Shrubs
Flowering bushes and trees suitable for the Northeast include ornamental cherry and plum trees, crabapples, dogwoods, mock orange, lilac, butterfly bush, cinquefoil, and spirea. Box honeysuckle, rhododendrons and azaleas add color to shady corners and north-facing foundations. Several varieties and colors of roses are suitable in the Northeast. The American Rose Society bestowed "outstanding" ratings to the hardy varieties "Dortmund," a red shrub rose; "William Baffin," a pink rose shrub; and two white rugosa-type rose bushes, "Henry Hudson" and "Rosa Rugosa Alba." Yellow shrub roses rated as "superior" include "Golden Wings" and "Graham Thomas."
Climbing, twining vines add colorful blooms just about anywhere you need them -- along a cement foundation, up a mailbox post, draping an arbor, over a gate, or even scaling a steep hill. Many of the more popular vines are hardy to the Northeast. Clematis varieties come in an astonishing variety of hues and shapes, and carry the additional benefit of being light enough to climb even flimsy structures. Most honeysuckle vines add fragrance as well as beauty to arbors, gates and even chain link fences, Use sturdier supports for rambler roses, wisteria and hydrangea vines.