carbon (C) oxygen (O) hydrogen (H) molybdenum (Mo) iron (F) copper (Cu)

cadmium (Ca) sulfur (S) magnesium (Mg) manganese (Mn) boron (B) chlorine (Cl)

nitrogen (N) phosphorus (P) potassium (K) zinc (Zn) nickel (Ni) cobalt (Co)

• increase survivability and growth height, but lessen biomass (due to decreased photosynthesis and root growth)
• seem to benefit selected species and selected planting sites, but have no beneficial effect on others
• force plant growth by increasing growth height, resulting in weak, thinner stems
• prolong the active growing season, which may decrease cold hardiness

Trees are an engineering marvel. How does a tree lift water from its roots to its top at a rate of up to 46 metres per hour and 380 litres a day? The job is done by a series of inert pipes called the xylem. How the xylem actually does this is not fully understood.

Equally amazing is that, pound for pound, trees and other plants need much more water to survive than animals do. For example, a sunflower must take up 17 times more water each day than a human of comparable weight would need. Of course, some plants do not need as much water as others, because they have built-in mechanisms that reduce transpiration rates or leakage through their leaf pores.

One of the indicators of good design is restraint. Believe it or not, the best landscape planting designs are very simple, with only a limited number of plant species massed into large drifts. An old design rule is: KISS (keep it simple, silly). Bad design and construction is just as expensive as good design and construction… so do it right the first time!

Landscape designs go through different design styles and trends, just like clothing and interior design. MPA strives for a classic, timeless design style, as opposed to the "flavour of the month/year" trend. Timeless design is simple, elegant, and restrained.

You've heard of "special mix"-type soils, sold by many nurseries. But unless you are growing annual bedding plants, stay away from it - as the ING guy says, “save your money.” Special mix-type soils are a mixture of top soil (a resource that is becoming scarce and valuable, like oil and gold), spaghnum peat moss (which nature takes 1,000 years to make), and manure or compost. You do not need it to grow most plants!

MPA will never specify "special mix"-type soil.

Sphagnum peat moss is dead organic material that has taken nature 1,000 years to produce. Despite what you may be told, it has no redeeming value to the landscape industry. Sphagnum peat moss is sterile, has few or no plant "nutrients," may reduce soil pH, and will not readily absorb water if it ever dries out (it will shed water instead). Well-rotted leaves or compost and clean, sharp sand are far superior soil amendments.

MPA will never specify the use of sphagnum peat moss.

Mulch can be your best friend.

Place mulch 75 mm to 100 mm deep. At this depth, it will reduce weed growth and keep moisture in the soil. As it decomposes, it returns essential elements back into the soil. The trick is to use shredded conifer bark mulch. Don't bother with wood chips, as this type of mulch will not knit together and may decay too fast. Be sure to keep mulch away from plant stems and trunks – avoid a ‘mulch volcano’ – to prevent stem rot.

Have you ever wondered why suburban landscapes all look the same?

This did not happen by accident. Colston Burrell, in the Spring 1997 issue of Wildflower, pp. 19 to 21, identified six suburban landscape characteristics:

• An unobstructed view to the front of the house
  A clear view of the front of the house and an unambiguous path to the front door is a holdover from the era of the great estates of Europe.
• Manicured turf on the front yard
  All great estates also had vast expanses of manicured lawns. A well-manicured lawn - a powerful and enduring landscape feature in North America - was intended to signify care, neighbourliness, and stewardship.
• Foundation plantings
  Foundation plantings did not exist prior to the advent of suburbia in the 1930s. They were initially used to hide the foundation pillars of houses that did not have basements or cellars.
• Street trees and a median, and one or more shade trees in the front yard
  Shade trees in the front yards of the great estates were used to frame the views of the façade, as decoration, to provide shade, and to draw the eye.
• Flower beds
  Flowers provide colour in an otherwise monochromatic green landscape. Because flower beds need human intention and care, they symbolize that the homeowner cares about the neighbourhood.

Paul F. J. Eagles, a professor in the University of Waterloo's Faculty of Applied Health Sciences, theorizes that the icon of the manicured lawn developed in Victorian England. Rural England at the time of Queen Victoria was a landscape of green, rolling hills where grazing sheep closely cropped the pasture grasses. Abundant English rainfall and nutrient-rich sheep droppings kept the grasses deep green.

To the poor, landless immigrants who flooded Canada and the United States during this time, the rolling green hills of the English estate were a symbol of wealth and social power. As North America became urbanized, the new urbanites wanted to retain this powerful symbol by having their own small sheep pasture around their "estate." With a little help over the next century from organizations such as the United States Department of Agriculture, the Garden Clubs of America, the United States Golf Association (as well as soldiers returning from the World Wars, and the marketing of lawn care products), the icon of the lush, green lawn became firmly entrenched in America.

In early New England, during the 17th century, street trees in settlements were perceived as dangerous because they provided hiding places for aboriginal attackers. Also, the village green needed to be open for militia manoeuvres and for herding cattle. Early subdivision development in the 1940s and 1950s did not give much thought to street trees and tended to use open fields.

The visual impact of a street tree lies in its crown volume. A tree must be large enough to give immediate shade; trees should be planted in sufficient numbers to create visual continuity. Therefore, plant either a few large trees or many smaller ones.

Can we afford to wait 50 to 100 years for a street tree to mature, in order to gain the right scale and visual effect? Will a tree planted today be alive in 50 years?

How often have you heard landscaping being equated with "beautifying" the urban environment? Saying this implies that trees, shrubs, and "flowers" are planted as add-ons, to make the urban environment "beautiful" or to "soften" the city.

Plants should not mask inept urban design or architecture; rather, they should be an intrinsic part of the urban structure. Plants can live without people, but can people live without plants?

Crime and social conflict is a concern in urban open spaces. Empirical studies have shown that physical features of an open space environment may influence perception of safety.

Long sight lines, open grassy areas, and water are associated with feelings of safety; on the other hand, dense vegetation, graffiti, and litter decrease perceived safety. Dense, unmaintained vegetation is perceived as scenic, but unsafe. Open athletic fields are viewed as safe but not very attractive. Open spaces with an overhead tree canopy but little vegetation at eye level to block views are perceived as both safe and scenic. Perceived safety is also enhanced when landscape plantings do not block the visibility of building entrances.

Graffiti, also known as tagging, occurs in areas that lack an identifiable owner, or do not exhibit some clue that someone is looking after the area – e.g., derelict, abandoned buildings or open spaces are often tagged.

Graffiti breeds graffiti; therefore, remove all traces as soon as it happens. Painting over it only provides a clean canvas and will only invite more graffiti. Maintain all facades and edges of buildings and open spaces to show that someone "owns" the space and cares for it.

Nothing lasts for ever.

Niall Kirkwood, in his book Weathering and Durability in Landscape Architecture, states that time alters a built landscape by the direct effect it has on the landscape itself. You can attempt to change this alteration through regular and persistent maintenance and reconstruction, producing a static piece of built work. This, however, is also a form of change.

Kirwood suggests that the effect of time can be registered, or shown, by deliberately proposing built forms that will fail or will have a restricted or limited life. Ideas about change come about from the selection and juxtaposition of materials, the methods of working the materials and their assembly, and the relationship and sequence of joints and junctions in materials.

Weathering, according to Michael Blier, ASLA, is defined as “the product of change that occurs as a result of the interaction of similar or dissimilar materials or actions to, or upon, one another that results in the creation of a third condition. This third condition is less predictable and far less stable than the original materials.”

It is sometimes difficult for our clients to understand that once the landscape is installed, it will immediately begin to change. Plants grow and respond to environmental conditions, and hard materials and finishes will begin to weather and/or degrade. This rate of change will be governed by issues of maintenance and accountability.

Public landscapes are much more subject to the variables of changing stewardship than private landscapes. Executive officers, managers, maintenance staff, and board members/governing councilors change. Each change represents a possible loss of "institutional memory" of why and how that landscape evolved. Maintenance budgets are often reduced, and neglect sets in.

Placement of street furniture such as benches is very important. Street furniture can be used to channel pedestrian flow and to encourage desirable behaviours.

Have you ever sat on a bench and, for some reason, felt uncomfortable? Maybe the bench itself was not comfortable to sit on. Chances are that the landscape architect chose that style of bench because the streetscape was designed to discourage you from lingering.

On the other hand, some seating areas encourage you to relax and enjoy yourself. One way to encourage lingering is to locate the bench in an alcove just back from the main sidewalk traffic flow, so that when seated, your back is facing a wall or shrub bed and you are facing outwards towards the street. This is known as the "gun-fighters position." The bench proportions fit you like a glove, the sun is shinning, you have some time to kill, and life is good – all by design!