Choosing the right plant for the conditions in the location is an important part of organic gardening. The right plant in the right location will thrive; plants planted in the wrong location will not do as well, if they survive at all, or will require more attention.
The Toronto area is in plant hardiness zone 6, using the Canadian system of classifying plant hardiness zones. Within the greater Toronto area you could be as low as 5a to 6b depending upon your exposure and proximity to the lake which moderates temperatures. To be sure that a plant will thrive you should air on the side of choosing one suitable for a slightly lower climate zone number.
A very good site for determining a list of plants that will survive in any Canadian climate is the website for Home and Gardens TV. By going to their map and turning off the display of everything but zone 5 (for areas north of Toronto away from the lake) or zone 6 (for areas in Toronto) you can get a list of plants suitable for these zones. http://www.hgtv.ca/gardening/plantzones/
Other sites dealing with hardiness zones include:
Bear in mind when you are choosing plants that native plants will generally grow better,
According to the Michigan State university, http://web1.msue.msu.edu/monroe/soilweb2/ph.htm ,most plants prefer a PH in the 6 to 7 range (slightly acidic), but some want an acid soil with a ph lower than this. The list includes several personal favourites. Among them are dogwood, azalea, rhododendrons, spruce, hydrangeas and holly.
Two favourites, rhododendrons and azaleas, in general, require an acid soil with pH about 5.5. Soils with pH higher than 5.5 should be acidified. http://www.rhododendron.org/soil.htm. In particular, we have attempted to grow a particular favourite, rhododendrons, in full shade (they do best in full sun to partial shade), climate zone 6 (7 is preferred) and soil that is alkaline without much success (3 failures 1 success and one hanging on. While rhododendens need to be kept wet, they should not sit in water, so a well-drained soil is needed.
Apparently, according to this reference. growing rhododendrons in a pine bark mulch containing little if any oil is practised in alkaline soils. So loving rhododendrons, we will try that this season and report on the results in the fall.
Also on the list are pine, red oak pin oak, and mountain ash.
From the same site, there is a longer list of plants tolerant of alkaline soils including trees and shrubs maples, blue beech, rose of sharon, junipers and viburnums and euonymus.
According to Agriculture Canada: and numerous other sources saying much the same thing organic material:
The university of McGill says much the same thing:
"Benefits of humus:
• supplies nutrients, especially nitrogen (N), phosphorus (P) and sulphur (S), when the plant needs them;
• holds nutrients, thereby reducing nutrient leaching;
• binds soil particles together, stabilizing loose soils against erosion;
• increases the friability (the ability to break the soil apart) of heavy soils; and
• improves porosity, thereby facilitating air and water movement, and increases the soil's water-holding capacity."
So be sure to add plenty of organic material to your garden, or ask the Lite Gardener to do it for you.
Everyone knows about the importance of matching the plants you choose with light conditions at that condition (full shade, partial shade and full sun. As indicated in the testimonials page on this web site the web master himself received an expensive lesson on the importance of doing this, when several cedars died altogether and other cedars went completely brown on only one side. The Lite Gardener immediately pointed this out and a bit of research at the local nursery confirmed that cedars will not tolerate full shade. The cedars that died were in full shade; the cedars that turn brown were shaded on the brown side. The greenside received adequate light. The dead cedars were replaced with Japanese yews, which the local nursery recommended as being tolerant of shade.
And the one success in growing rhodendrons (3 failures, 1 success, 1 maybe) received more light than the failures. The one that died were planted in full shade. The one that is thriving receives sun for the latter part of the day. It took 2 years to become established, so conditions (ph) where I planted it maybe suspect. I will be asking the Lite Gardener to do a soil test for me. Pictures of this plant will be provided once it blooms.
The lesson learned: - check the light requirements of a plant before choosing it for a particular location. Failing to do that can be expensive.
One of the best things I did for my lawn and for the look of my property in general was to install an irrigation system which comes on automatically, because I was too 'busy' to do the job manually by watering systematically.
The recommendations are enough water to with the soil to about a depth of 6 inches, which requires about an inch of water. Then don't water again until the soil dries out a bit. Watering too frequently encourages shallow root growth.
Do not over or under water.
Until I replaced the lawn with a garden in areas shaded by three large spruce trees I had mildew and mushrooms growing, as a result of water sitting on the leaves to long. Applying water in the heat of the day will just result in a large amount of evaporation and applying water in the evening can lead to mildew, as a result of water remaining on the leaves too long. The best time is in the early morning.
Of course, the primary object is to have a nich looking garden landscape. Plants that thrive in a given location are obviously a "necessary but not suffiient condition". In choosing matching your plants with location you need to follow god landscape design principles, as well as paying attention to factors such as hardiness zones, soil conditions, soil humus, light and water.
You need to place your plants in the garden with the highest plants in the back. You need to group plants of a kind together so that you garden consists of groups of similar plants, rather than a random selection. Transitions between one grouping and another need to be considered. You need to respect the plant space requirement - some plants spread out, others require less spacing between plants.
When groups of plants bloom is another important consideration. Ideally you want to have colour in your garden year round, either from voliage or from flowers. The colours should work together.
Actually they are many elements that work together to create "good landscape design principles". If you do a search you will find many that deal with this issue. One of the better ones visited was: http://www.northscaping.com/Tools/LG/LandscapingGuideCh2.shtml but find out for yourself.
So planning the layout of your garden is important before you choose plants, and certainly before you plant them, or have the Lite Gardener do it for you.