It goes without saying that heaths are colorful, versatile, and useful year-round evergreen shrubs. But you may not know the winter-blooming heaths, which add a splash of color to gardens throughout winter. These hardy, low-growing plants produce a wide variety of bell-shaped or tubular pale pink, reddish purple, and magenta flowers for what seems like an eternity -- October and November into April and May. And the heath foliage itself paints your landscape with colors ranging from pale greens and soft yellows to light shades of copper, bronze, and gold.
Properly selected and planted, winter-blooming heaths grow almost anywhere, from Maine to Florida and Alaska to Hawaii. They work well in borders, with other small conifers and shrubs, in rock gardens, or perhaps best of all, by themselves. In northern snowbelt areas, (USDA Hardiness Zones 3 through 6), heaths actually bloom under the snow, their flowers revealed as snow recedes in early spring. If you live in these regions, choose varieties that are in bloom near the beginning or end of the snowfall season (see list of varieties below).
Heaths (cousins of the true Scotch heathers, Calluna vulgaris) include three groups of winter-blooming varieties and more than a dozen other summer-blooming types. All are members of the large Ericaceae family, which also includes rhododendrons, azaleas, and blueberries.
Hardiest and most readily available of the winter-blooming heaths are varieties of Erica carnea. With winter protection many varieties thrive in zone 4 (to -25° F.) and sometimes even in parts of zone 3. The bushier E. darleyensis varieties are usually hardy in zone 5 (-20° F.). Least hardy are varieties of E. erigena, which are more difficult to obtain and are usually hardy only in zones 7 (0° F.).
Also called snow heather, spring heath (Erica carnea) is native to mountainous areas of eastern Europe. There, plants thrive in coniferous woods and on stony slopes, and in spite of harsh winterconditions. Their prostrate habit and fast growth make them excellent plants for a rock garden, on a slope, filling in a heather (Calluna) garden; they also make long-blooming companions for other plants. Most of the nearly 100 named varieties are low and carpeting, 6 to 9 inches tall with a spread of 2 feet or less. Some bushier varieties may reach a foot in height and spread about 2 feet in diameter. Well-established plants require very little attention and form a weed-smothering carpet.
Some varieties start blooming as early as November, and others early in the new year. Most finish flowering in late May, and within days begin to set buds for the next season.
Blossom colors vary from white through pink and lavender to deep reddish purple and magenta. Many darken with age to give a bicolor effect. Foliage ranges from golden yellow and pale green to deep or grayish green, sometimes with streaks of gold on the leaves. Some kinds sport cream or pink tips on new growth. Flower buds form in summer but may take as long as nine months to bloom. Actual blooming times depend a lot on the climate. When winters are mild, flowers tend to open up to two months earlier than when winters are harsh.
Microclimates and gardening techniques can make a big difference in both blooming time and amount of bloom. Even in the same garden, plants in protected locations or in raised beds or amended soil often flower much earlier than the same plant in natural soil or in an exposed location.
These have a long flowering period, are suitable to almost any soil, and need very little pruning to remain neat and compact. Heights range from about 8 inches to almost 2 feet. Most are neatly shaped bushes that spread from 1 to 3 feet, depending on the variety. Many varieties have pleasing pink or cream tips of new growth in spring, and some foliage is accented with bronze tones in winter. Buds form in late summer or very e fall, and some varieties begin blooming as early as September often continuing well into May. As on E. carnea, many flowers open pink and deepen to reddish purple as the season progresses.
Most varieties of Irish Heath (Erica erigena) bloom in late winter or in spring. They are less hardy than the other two winter-blooming heaths and are often much taller, at least 3 feet and up to 12 feet tall. They are also more difficult to find. The branches of Irish heath tend to be woody and brittle, and will snap under heavy snow loads.
Because heaths have fibrous, shallow roots, so plants grow best in sandy, well-drained soil. Add peat moss or compost to improve drainage, or plant in raised beds or mounds. And as for other plants of this family, they need slightly acidic soil. If your soil is alkaline or nearly so, use fertilizers recommended for azaleas and rhododendrons, or similar acid formulations. Winter-blooming heaths can also be planted in containers but don't perform well inside the house or on a shady porch.
Plant heaths in full exposure to the sun. Plants can tolerate partial shade, but they won't bloom as well and tend to get leggy.
In most areas, early spring or early fall are best planting times. Prepare a hole at least twice as wide as the size of the rootball. Partially fill the hole with compost or topsoil. Don't plant too deep! Heaths have shallow roots and do best if planted at about the same depth as they grow in the pot. Water well after planting.
Good drainage is important. Scoring or lightly scratching the root ball in two or three places helps plants establish quickly. Established heaths are quite drought resistant, but failure to water adequately the first two seasons is the prime reason for plant loss.
Winter-blooming heaths require very little pruning. It is safest to prune, when needed, as soon as flowers fade because buds are set almost immediately for the next season. To encourage compactness and flowering, prune around the edges of the plant and very lightly over the top. Spring pruning may also be necessary to repair winter damage. Clip off broken or dead branches, and shape the plant. Heaths can take severe pruning when necessary but can be damaged if heavily pruned before hard frosts.
Winter protection is necessary where subzero temperatures are common, particularly when they occur before significant snow accumulation. If your plants will be exposed to months of severe cold, use evergreen boughs, straw, or canvas to protect them from cold or from drying winds. Avoid heavy mulches, such as leaves, which will mat and possibly injure the plant. Anti-desiccant sprays can also be applied.
A light application of acid fertilizer in spring is usually enough. A granular type that can be watered into the soil is best. Don't apply fertilizer to the foliage, and keep it at least two inches from the stem.
Heaths are easy to grow and have few natural enemies. However, well-drained soil will help prevent root rot, or erica wilt (Phytophthora cinnamoni). This fungal disease kills the roots, causing the foliage to wilt and die. Fungicides are available, but prevention is ultimately easier.
Unless otherwise noted, all of the E. carnea selections are low (less than 12 inches), spreading, and bloom from January through May.
'Foxhollow Fairy': bicolor pink January-March. Medium green leaves.
'King George': pink flowers December-March on compact dark green bush.
'Pink Spangles': bicolor shell pink with medium green foliage.
'Porter's Red': attractive magenta flowers on dark green foliage.
'Sherwood's Early Red': ruby flowers November to February. Dark foliage.
'Springwood Pink': pink blooms on medium green foliage with bronze tips.
'Springwood White': masses of white flowers on bright green stems.
'Vivellii': bushy with heliotrope flowers and dark foliage.
'Darley Dale': light rosy purple flowers September-May deepen with age; 24 inches tall.
'Darleyensis Alba' or 'Silberschmelze': white blossoms September through May. Medium green foliage has creamy tips in spring; reaches 15 inches.
'Furzey': deep rose pink flowers October through May. Dark green foliage has pink tips in spring; to 18 inches.
'Jack H. Brummage': heliotrope flowers January through May with yellow-orange foliage; low, spreading.
'George Rendall': pink to heliotrope flowers November to May; medium green foliage with red, pink and cream tips in various seasons; reaches 14 inches.
'Ghost Hills': pink flowers between November and May deepen to heliotrope; cream-colored tips on medium green foliage in spring.
'Irish Dusk': salmon buds open clear rose pink November to May. Bushy, 15 inches tall, dark gray-green foliage.
'Superba': shell to deep pink mildly fragrant flowers April to June; tall bush (60 inches) with 24-inch spread; dark green foliage.
'W. T. Rackliff': white flowers January to April; neat and compact, 12 inches tall, with spread of 24 inches; bright green foliage.
Article published on June 23, 2008.