Create a woodland oasis. (2003 Feature Section--"Themes and Extremes").
I have viewed many public and private gardens and what transforms a mere shade garden to a magical woodland oasis is often missed. From the earth to the sky, every element has its purpose. What unfolds is how to replicate this unique ecotype.
Soil is the one most important element. With the correct texture and type of soil a woodland can thrive. It should be rich in organic matter but well drained with a wonderful earthy aroma. Typical prairie soils can be heavy clay or moisture/nutrient poor sand. Fortunately amendments are available to help. The three I have found most useful are peat moss, compost and Fuller's earth.
Peat moss from sphagnum is preferred to all other peat. A generous layer 4" to 6" mixed into existing soil works well to enrich sandy soils but can bog up heavy clay. Because of it's fine texture it also breaks down quickly and must be added to yearly to keep soil in fine form.
Compost, particularly from broken down wood products is excellent. It has a similar texture to natural woodland soil, somewhat coarse, so it works well with both sand and clay soils. It breaks down slower than peat so can be added every second or third year.
Fuller's earth is used extensively in the US for pro sports construction, golf courses, baseball diamonds, and football fields. It has a twofold purpose. As fired granules of clay it provides very good drainage much like coarse sand. However unlike sand, it can wick and hold water, storing it to release as the soil dries, when the plants need it most. It works extremely well with both clay and sandy soils. New to the home gardener, it is sold under the brand name "PROFILE". More costly than the other two amendments initially, it does not decompose thus never needs replacing. I have found it to be the best amendment for permanent soil improvement. My personal preference is to use all three to create a perfect blend.
Allowing leaf litter to accumulate goes a long way to keep the soil in top form. The natural decay process softens existing soil, adds nutrients and encourages other creatures to enjoy your woodland.
Topography, or the lay of the land, is next in planning your woodland oasis. It should be gently undulating with low spots for moisture loving plants and a few slight inclines for early bloomers such as bulbs.
Layers of plants are important to woodland. They give it depth and shadows. They muffle outside noises, create shade and keep the temperature cooler than the surrounding area. There are four primary layers to keep in mind while planning your woodland. (see diagram below).
Canopy layer is comprised of the major trees. Evergreens produce dense shade year round while deciduous trees leave openings for early bloomers and create a more dappled shade. Sub-canopy layer is smaller trees, large shrubs and even vines. They add shadows and a rich backdrop. This is the most important layer for sound control. The more numerous and closer spaced the more muted outside influences become.
Under story layer is the perennials and low shrubs that provide the close up visuals.
Carpet layer is ground cover plants, mosses, mulches and pathways. In my childhood home it was always soft under foot, producing little to no sound when trod upon. No bare earth should show but rather the years of natural decay produce a wonderful cover necessary to hold moisture.
Plantings should be simple but in mass. In true woodland, plants grow in groups where conditions allow i.e.; a low patch of ferns, gentle slope covered in wood violets, or crocus and scilla beneath a deciduous tree. Understated is the key. The overall picture should be like a faded tapestry, rich and subtle not a crazy quilt of contrasting clashing colours all demanding your attention.
Ah! The plants. There have been so many breakthroughs in cold tolerant woodland and shade plants. There is virtually no end to the varieties available. When people from warmer zones visit Parkland Nurseries and ask me `Can't you grow anything here?' I take them on the long tour. I love to dazzle them with benches of lush hostas, astilbe alive with their feathery blooms, ligularia towering overhead, vincas, violets, bearberry, cliffgreen, trout lily and of course lady's slipper. While their heads are still reeling, I sweetly ask "Now would you like to see the shrubs?'
All kidding aside, my two favorites from Vancouver Island, rhododendrons and heucheras have made the most impressive impact in recent years.
The University of Helsinki in Finland has been intensively breeding rhododendrons since 1973. Dedicated researchers such as Anu Vainola M. Sc. have produced nine cold tolerant cultivars. Six of these are especially suited to the prairie regions and will be available at Parkland Nurseries and Garden Centre for spring 2003. They are Elviira, Haaga, Helsinki University, PMA Tigerstedt (also known as Peter Tigerstedt) Pohjola's Daughter and Mikkeli. For a look at these rhododendrons, you can visit her website at: http://honeybee.helsinki.fi/users/avainola/rhodo/cultivars.htm
Heucheras have also been transformed over the past ten years. No longer a backdrop plant, the new heucheras are lush and vibrant with colours once thought impossible. The best part, when the flowering neighbors have faded away, the foliage continues on heucheras warm, rich throughout the season. My favorite recent cultivars are Amber Waves, Cherry Pie, and Plum Pudding.
The next time you wander through a wooded area, think of its potential. Maybe it's not just a shelterbelt. That native stand of birch or poplar could hold magic if you start from the ground up.
Pat Aldi CCHT (Canadian Certified Horticulture Technician) is the Information Centre Coordinator at Parkland Nurseries & Garden Centre in Red Deer, Alberta. She provides advice, diagnostics and a listening ear to gardeners all over Alberta.
|Printer friendly Cite/link Email Feedback|
|Date:||Jan 1, 2003|
|Previous Article:||Gardening on the edge in the Chinook Zone. (2003 Feature Section--"Themes and Extremes").|
|Next Article:||The Meditation Garden and Perennial Border at the Forestry Farm Park, Saskatoon. (2003 Feature Section--"Themes and Extremes").|