“That which we call a rose, by any other name would smell as sweet”….. Shakespeare
Damask, Moss, or Gallica? Â Modern, Old or English? Call them what you will, many gardeners fall in love with roses early on, and the infatuation never ends. The moist, velvety petals and heady fragrance of this fabled flower are powerfully seductive.Â Â It is easy to to understand the allure of roses. A garden in June, with roses climbingÂ walls, tumbling overÂ fences and nestled into perennial borders, is a beautiful sight.Â During the long, dark months of winter, many northern gardeners curl up with spring catalogues, fantasizing about the vast array of rose offerings. Â I too have been tempted by this fragrant queen of flowers, and having succeeded in my first garden with a luxurious climbing-beauty named “Constance Spry”, I know the sweet rewards of success. But as a professional gardener, I also know that growing roses can be a real challenge in cold climates. And unless the rose-lover takes as much care in the planning and planting phase as he/she does in the dreaming stage, there will often be great disappointment. Healthy, vigorous roses of almost all types can be grown in New England with a bit of research and proper care. The first steps in successful cold-climate rose culture are choosing the right location for the rose within the garden itself, and of course,Â selection of the best plants for hardiness
Choosing and siting a rose with it’s individual lifetime requirements in mind is wise for many reasons. Â A rose planted in a proper site will receive ample sun, water, nutrients and protection. Â The site should also allow the rose enough space to reach its full size and shape, and provide ample air movement for healthy foliage and adequate drainage of soil for healthy roots. Focusing on the process of gardening, by providing a proper environment, is key to success no matter what the gardener wishes to grow.
Soil is important to all plant life, of course. Â And roses, like most plants, have preferences about the soil in which they grow. Â It is wise to test your soil pH level, as well as nitrogen, phosphorus and potash levels, and adjust your soil chemistry accordingly. Roses prefer soil rich in minerals, nutrients and organic matter. Â Like most garden plants, roses prefer a slightly acid soil with a pH between 6 and 7. When soil pH becomes too low or too high, nutrients become less available to plants. A pH test is easy to do, and takes just a few minutes. Soil testing kits are readily available at most garden centers and through online vendors and more extensive soil tests can often be done through your local university extension service. Getting pH and nutrient levels right is the first step toward making sure that your roses are receiving what they need from the soil in order to grow and thrive.
Soil texture is also very important to roses. And while it is true that roses prefer mineral-rich soil, it is also critical that they receive proper drainage and air circulation at their roots. Â For these reasons, it is often helpful to closely examine your garden soil, and modify the texture if necessary, before planting roses. Â Clay rich soils provide the minerals roses prefer, but unless organic matter, (such as compost and peat moss or other fiber), is added to the soil,the rose will rot and suffocate in water-logged, poorly aerated root conditions. Conversely, sandy soil will provide the rose with the drainage and dry roots it prefers, but the plant will suffer as minerals and nutrients wash away from the roots in quickly draining sand. Organic matter such as compost and other fibrous materials will hold moisture, minerals and nutrients in the soil, allowing the plant time to absorb them into it’s root system. Â Adding compost and other organic material will improve your soil, be it clay-like or sandy.
Protecting the root zone of roses in climates like New England,where wildly fluctuating temperatures are common, will help prevent many problems. Compost-mulch shields roots and soil from heat and cold, weeds and insects, wind and erosion. Â Bare soil is not natural, and stresses plants. Caring for the parts of the rose beneath the ground is as important as the attention we give to the plant we see. The rewards of good soil-science are strong, healthy root systems and roses with access to good nutrition. a few inches of compost mulch, and perhaps the addition of herbal companion plants such as thyme and lavender, (herbs provide some natural insect resistance, and attract beneficial insects), will go a long way toward giving your rose ideal growing conditions.
Of course, what goes on above soil level is equally important to rose-culture. Full sun is an absolute requirement for healthy roses. The plant should receive bright light from sunrise to sunset. Without full sun, a rose can not properly photosynthesize, and the result is a weak and spindly plant with few blossoms. Sunlight is also critical for dry foliage, and dry foliage is key to preventing fungal infections and disease. Although some rose varieties will tolerate less than a full day of sun, no rose is truly happy in shade. Sunny-sited roses will always be stronger and healthier than their shadowed neighbors. Give the rose what it needs, and it will return the favor of what you want: blossoms.
Considering air circulation and flow is advantageous for plant health, and longevity. Â Siting your rose for unobstructed growth and air movement is important for disease prevention and cold protection. Â Roses protected from prevailing winds by taller trees and shrubs will grow stronger and avoid the damage of winter desiccation. Â So long as neighboring plants do not obstruct sunlight, roses will benefit from the back-up provided by neighboring hedges or groups of shrubs. Â It is also beneficial to plant roses on a slightly elevated portion of a site. Â Cold air flows downhill, and frost settles in lower parts of the land first. Â Siting roses in a raised position will help with both airflow and drainage, giving roses another advantage in a cold climate.
Providing roses with the correct growing conditions is clearly important. However, no amount of care and consideration can substitute for proper selection of the rose itself. Â When selecting roses for any garden, it is important to first consider the uniqueness of the plant. Every rose has an individual habit, mature size, shape and texture. Â Some roses are vigorous and shrubby, some are politely contained bushes. Certain roses are open-shaped, others are dense. A few roses may be grown as climbers or tall shrubs, others remain petite. Knowing the form of the plant will help the gardener decide if it is right for the garden’s design. Rugosa roses have very different requirements from English roses. Â And of course, any rose grown in a climate with cold winters must be fully compatible with the garden’s USDA hardiness zone.
As most gardeners quickly become aware, even individual gardens can have micro-climates with enough temperature variation to make a major difference in cold-hardiness. Spots protected from prevailing winds and freeze-thaw conditions on an individual site may allow for some zone-flexibility. Â However, given the temperature variations in New England, it is safest to stick with a conservative attitude toward cold-hardiness, unless the gardener is willing to take extra precautions by mounding rose-root zones with compost each fall, and in some cases providing protection for the entire shrub. Â New rose varieties will be more variable than the tried and true, and for the beginning gardener, hardy and time-tested varieties are a good place to start. Â USDA zone 4/5 roses are a safe bet for most gardeners in New England, and zone 2/3 varieties will be safest for very cold, windy or exposed sites.
Most rugosa roses, modern landscape roses, and many antique shrub roses are extremely cold hardy. Rosa rugosa “Sarah Van Fleet”, “Belle Poitevine” and “Blanc double de Coubert” and hybrid “Therese Bugnet” are beautiful, exceptional performers. Â Rugosas are a good choice for fences, hedges and groupings in the landscape. David Austin English roses are a nice choice for mixed borders, and provided the bud-union, (point of graft), is planted at least 4 inches beneath the soil-surface, a well sited Austin rose will perform well in New England. Â Tried and true landscape roses, such as “Carefree Wonder”,( and for small-bloom lovers, “The Fairy”), are excellent selections for a wide variety of perennial garden designs, including designs with stone and along walkways. For old rose lovers, the hardy gallica, alba, moss and damask hybrids are good bets. “Charles de Mills”, “Konigin Von Denmark”, “Karl Forster”, “Maiden’s Blush”, “Striped Moss” and “Stanwell Perpetual” bring some old European-style to northern rose gardens.Â In addition to the shrub and landscape roses mentioned above, some climbers such as Â “William Baffin”, “New Dawn” and “John Cabot” are tough enough to weather the cold winds and blistering sub- zero temperatures New England dishes out. Extra care must be taken when siting more marginal climbing roses, such as “Constance Spry”, in a cold climate. Â It is important to protect the exposed canes of more delicate climbing roses from desiccating winter winds. And always remember to position your rose to avoid damage from snow loads sliding off a steep roof.
When purchasing potted roses, try to buy from a local nursery, where the growers know your zone hardiness and purchase or propagate roses with cold conditions in mind. Take the time to ask the garden center staff about the roses you buy, and research the variety online to learn its habits and preferences. Knowing your rose and giving it what it needs are key to success no matter the garden climate, however this advice holds particularly true for gardeners in the north, where roses named “cold hardy” will continue to smell sweet for many years.
( coming soon…. part two roses: planting, pruning and maintenance )
Copyright 2009 Michaela H