Alpines, miniature miracles
They hug the ground, many of them, as if to embrace Mother Earth and thank her for their sustenance. Others are braver, rising six to eight inches into the air, seeking support from the sun and revelling in the air that moves gently around them. Most are beautiful – exquisite may be more accurate – requiring an up-close and personal relationship to truly appreciate.
These are the alpines, the plants that populate altitudinous slopes just below the snow line around the world. Many are covered in air conditioning fuzz, others are coloured blue-grey to regulate heat exposure. In gardens, they serve as ground covers (think of carpets of woolly thyme) or as borders (think of sweet alyssum) or they tumble over boulders and stones in miniature rockeries.
Alpine plants are survivors and they have developed many mechanisms to cope with extreme heat and cold, high winds and burning, unmitigated exposure to the sun.
Many alpines have a network of hairs on stems or leaves. The hairs are called trichomes and they act like tiny air conditioners, regulating the air temperature at the surface of the leaf by as much as 10 degrees C. Other alpines take on a silvery or grey-blue hue, which helps to reflect the sunlight. The low stature of these plants protects from damaging winds.
Their roots systems are often quite deep, to enable the plants to find nutrients and water in crevasses and cracks and to provide good anchorage against the fierce winds. Stems may be wiry and tough.
Some have a habit of growing in mats as closely packed clusters or as cushions as another way of maintaining heat and moisture. The density of the leaves and the shape of the plants both help to protect from ice penetration and water run off down steep slopes.
Alpines are best displayed at eye level or in some type of raised bed. While many of us don’t want the expense or bother of building a rock garden, containers such as troughs, as long as they have good drainage and a good support system, can be a good choice.
The container should be deep enough to allow the plants to form good roots systems.
Alpine plants need good, fast drainage, bright light and low organic matter. They need protection from winter moisture and will die of root rot if conditions are too moist. They need good aeration for their roots. If planting in containers, use gritty mixtures containing 50 per cent to 90 per cent inorganic materials such as 1/4-inch or smaller gravel and other grit.
If you are gardening at ground level, alpines combine well with dwarf evergreens and shrubby herbs such as rosemary, heathers or lavenders. You can use these plants to create a stunning checkerboard garden between pavers. An alpine garden can also solve that problem about what to do in the arid, rocky place that seems to proliferate in between houses in newer subdivisions.
Alpine plants do very well in many areas of the province. Places situated, like Calgary, at higher elevations,( average elevation in Calgary is 3,700 feet), are able to provide conditions similar to those that alpines experience naturally. One thing is certain: you will fall in love with these miniature miracles.
The Calgary Rock and Alpine Garden Society are a wonderful group to join if you are an alpine enthusiast. Visit craigs.ca for more information.