Landscaping extends the living space of your home, adding value to the property by creating spaces for relaxation and outdoor pleasure. But when you’re planning and maintaining your outdoor living space, remember to minimize the impact on resources, water quality and your health by using natural maintenance techniques, choosing the appropriate mix of plants and properly managing your rainwater. You can “green” your entire property and at the same time cut down on maintenance requirements, save time and save money.
Cedar: Cedar has great natural resistant to rot, mould and insects. It has a lifespan of over 25 years outdoors. It can be left in its natural state, but to prevent it from turning grey, it needs to be stained every 3 to 5 years.
100% recycled wood and plastic composites: they can be cut, sawed and used like wood. They won’t rot, they require no stain or paint, and they’re available in a variety of colours.
Heat-treated wood: kiln-baked to a very high temperature, heat-treated wood is completely dry and waterproof. It contains no chemical products, is rot resistant and lasts 50% longer than pressure-treated wood. Supporting members need to be reinforced, however, because the heat treatment reduces the wood’s resistance to static flexion. Waterproofing treatment must also be applied. This process can be used for most wood species. Choose wood from FSC certified forests to support sustainable forestry.
Choose low emissions or VOC-free coatings, paints and stains, to help reduce GHG emissions and harmful effects on your health.
For projects made of wood, minimize perforations and make sure the planks are arranged to facilitate runoff and quick drying. Choose screws that are suited to the type of wood and the right hardware, to avoid anchoring wood to concrete.
Since December 2003, wood treated with chromated copper arsenate (CCA) has not been produced in Canada for residential uses, because it contains arsenic.
Concrete flagstones and pavers are durable products that can be recyclable as aggregate, but they demand a lot of energy to produce and transport. Choose quality products so you can amortize those GHG emissions over a longer lifespan. Other eco-responsible choices are available to reduce the environmental impact of creating walkways and patios.
Choose natural stones mined and shaped locally, to reduce the GHGs related to their transportation. Natural stones come in several colours and textures, in random or regular shapes. The joints between the stones can be filled with polymer sand or groundcover, to suit any style.
When choosing flagstones or pavers, select honeycombed products that do not cover the entire soil. Vegetation can be allowed to grow up through the open sections of these water-permeable products, or the openings can be filled with fine gravel. This provides the triple advantage of reducing resource waste, lessening the effects of thermal islands and encouraging rainwater filtration into the soil, reducing the load on public infrastructure.
For wide vegetation-free surfaces like patios, choose white or light coloured flagstones or pavers, to lessen the effects of thermal islands, which lower air quality and can have a negative impact on your health. Buying products made with recycled content helps reduce resource waste and the flow of garbage to landfills.
Soil irrigation, unlike sprinkler systems, reduces the water consumption of landscaped gardens. There several different irrigation techniques, so before you choose one, make sure it complies with local municipal watering guidelines.
Cover the soil in flower borders with mulch. This helps prevent the growth of weeds and also keeps the soil moist, which encourages the microbial content of the soil, protects friendly insects and reduces the need for weeding and herbicides. Choose organic mulch: when it decomposes into humus over time, it will add organic substances to your soil. Some kinds of mulch, like those made of wood, have a longer lifespan, while others, such as straw and leaves, decompose more quickly.
Install a high-efficiency irrigation system. Some systems are complex and require the help of a professional. Others, such as soaker hoses placed on the ground, are simpler and can be installed using a timer. These irrigation systems save water and also reduce the impact associated with treating and pumping water.
When landscaping your property, it’s best to encourage the natural absorption of rainwater into the soil. Waterproof surfaces, such as unistone, concrete and asphalt, increase the effect of thermal islands and surface runoff. Rather than being absorbed into the soil, the water leaches contaminants from the streets and then runs into the sewers or directly into waterways. It’s important to avoid this impact on our water resources.
Maximize permeable areas such as green space, kitchen gardens and flower borders, to allow rainwater to be absorbed naturally, filtering out chemicals and preserving water quality.
When choosing flagstones or pavers, select honeycombed products that do not cover the entire soil. Vegetation can be allowed to grow up through the open sections of these water-permeable products, or the openings can be filled with fine gravel. They have the triple advantage of reducing resource waste, lessening the impact of thermal islands and encouraging rainwater filtration into the soil, decreasing the load on public infrastructure.
Other landscaping strategies can boost the “green” level of driveways, such as installing running strips (two pavements strips for the tires) surrounded by greenery, or a honeycombed plastic base that allows grass to grow up between it but supports the weight of the car.
A residential system that recycles greywater (water from showers, baths and sinks) or harvests rainwater can lead to water savings of about 146,000 litres a year for a 4-member family that uses appliances regularly. That’s enough to fill 3 aboveground swimming pools. Installing these 2 systems will reduce annual water consumption by about 33%.
Rainwater harvesting systems direct the water from the roof gutters into tanks for storage. It can then be reused for activities that do not require potable (suitable for drinking) water, such as watering the garden, washing the car or supplying toilets. Water that is reused for toilets must be filtered and treated to prevent the build-up of bacteria, which would have an impact on resources and water quality. Harvesting and using rainwater can save water and reduce the pressure on public utilities.
Creating a rain garden is another way to re-use water: the gutter downspouts are directed to a depression located at least 4 metres away from the foundation and filled with indigenous plants that can withstand drought and occasionally flooding. The water must be able to filter through quickly (24 to 48 hours) to avoid creating a breeding ground for mosquitoes. You’ll need the help of a professional to create a garden of this type.
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Transforming organic matter into compost can reduce the volume of domestic waste by over 30% and also cut down on GHG emissions related to the transportation and landfill of organic waste. Compost is also a great resource for flower and kitchen gardens. Composting harnesses the natural decaying process to turn organic waste into humus, a natural fertilizer. Leaves, garden waste and some kitchen scraps can be used. Well managed compost is odour-free and made up of 2/3 dry materials (leaves, grass cuttings or straw) and 1/3 kitchen scraps.
Choose a model for the backyard composter: micro-organisms and insects will take care of changing the organic materials into compost. Done properly, composting reduces emissions of methane (a powerful greenhouse gas) into the atmosphere, compared to landfill.
If you cannot compost outdoors, vermicomposting is another option. This method uses worms called red wigglers in a plastic bin inside the home.
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Grass clippings can represent up to 25% of the waste products generated by a family each year!
Setting up a little kitchen garden where you can grow vegetables, herbs and even fruit trees will give you the pleasure of harvesting your own crops. Urban agriculture can reduce the environmental impact of your diet by replacing pesticide-laden products that have been transported long distances with ecologically grown produce from your own backyard.
Plant vegetables and herbs that suit your climate and garden type. Vegetables generally prefer sunny, well-drained locations that warm up quickly.
If the backyard is not ideal for laying out a garden, very effective gardening tubs are available to grow vegetables on patios, roofs or right on the ground.
Plant fruit trees: they produce flavourful fruits in summer and beautiful blossoms in spring. Choose the right tree for your plant hardiness zone and soil type, to ensure healthy growth and reduce the need for chemical products.
Although soil texture and pH can be corrected, it is generally simpler to choose plants that are adapted to the soil type and climate, to reduce resource use and the amount of garbage that gets sent to landfill. To determine your plant hardiness zone, check the Natural Resources Canada atlas(@SIDLEE: Insert link). Local or indigenous plants are better suited to local climate conditions (temperature, ground frost, precipitation, snow, wind). This makes them stronger and easier to maintain, and they need less watering. Plants can generally adapt to slightly warmer zones, but they may not survive winter in a colder zone unless they are wrapped and mulched to withstand the cold.
Choose perennials over annuals. They have a much longer life cycle and you can divide mature plants. Your flower borders will change and develop from year to year and all you’ll have to do is maintain them.
To be healthy, plants have to be in balance with their environment. For example, soil that is too acidic or otherwise inappropriate can prevent plants from absorbing nutrients and encourage diseases. Working with your soil constitution and sun conditions can cut down on wasted resources. Although soil texture and pH can be adjusted, it is generally simpler to choose plants suited to the soil you have.
Do a soil analysis to make the appropriate corrections. Overly acidic soil can be modified by applying wood ash or lime. Soil that is too alkaline will benefit from an application of sulphur, ferrous sulphate or even pine needles. Soil texture is related to the size of the particles: if the particles are large, the soil is sandy, if they are very fine, the soil is clay. Soil texture can be corrected by adding things like compost or manure.
Every plant needs a specific amount of light to grow and produce flowers and fruit. If sun exposure is insufficient, the plant will produce fewer leaves, flowers and fruit, and may even die, as it will be more vulnerable to disease and insect pests.
Plants have all sorts of characteristics you can benefit from. For example, plants with strong root systems are very useful for retaining slopes, and climbers can be used to camouflage unattractive metal fences or poles.
Some plants make good neighbours. Putting herbs next to certain plants can camouflage them and confuse insect pests, for example. Companion planting, as this is called, is a great way to combat insect pests naturally.
Trees absorb sunlight, carbon gases and other pollutants, reducing the effects of thermal islands and protecting your health. But since they have such a long life cycle, it is important to plan the long-term development of the trees you plant and consider the way they’ll change your property.
Ornamental plants are beautiful additions, but they also add coolness in summer and absorb pollutants. Air pollution is a serious environmental and even social issue, especially in urban areas, and homeowners can be part of the solution by planting trees and shrubs.
In summer, deciduous trees block the light of the sun and provide shade to soil and the home. In addition to promoting biodiversity, they also reduce the need for air-conditioning if they are strategically placed in front of south-facing windows, for example. When winter comes, the leaves fall, allowing the sun’s energy to warm the house.
Do some research to choose the right tree species and the right location. A tree that will grow tall should not be placed under electrical wires, while a tree with deep roots should not be planted near underground pipes or wires or close to the swimming pool. You should also avoid planting trees too close to the house, as they may damage the foundation.
Grass just can’t grow well everywhere. You can reduce your impact on water by choosing plant species that need less. Choosing biodiversity over the monoculture of a traditional lawn also helps reduce the impact of landscaping.
Reduce the size of the lawn by replacing some of your grass with other plants, such as groundcovers that are better adapted to shady or very sunny spaces. This will also cut back on maintenance requirements, since these indigenous plants need less pampering, don’t have to be mowed and usually require little fertilizer. They also tend to choke out weeds.
Encourage biodiversity within the lawn itself. A healthy lawn should contain several plant species: choose a mix of resistant grasses or plant clover among the grass. Since insect pests generally prefer a particular species, mixed plantings make the lawn less appetizing for them.
The natural topography can be used as an asset for landscaping: a low spot can become a water garden, a mound can provide the foundation for a little outdoor hideaway, and a big stone can add a natural touch. Consult with a landscaping professional to make the most of the natural topography of your property, reduce resource use and minimize your impact on water.
Keeping the soil intact helps prevent deterioration and destabilization, reducing the possibility of erosion and the impact on water.
Leave streams in their natural bed. Water tends to return to its natural place, and trying to change its course could create erosion problems and have a negative impact on local flora and fauna.
Maintain the plant cover on stream banks: plants along streambeds are not just pretty, they also filter contaminants, provide an appropriate environment for various kind of wildlife and reduce the sedimentation of the waterway.
Choose strong tools that support sustainable forestry and reduce the impact of waste production, to reduce resource waste.
Tools made of wood from certified forests promote respectful resource management and ecosystem conservation.
Using recycled materials allows waste to be re-used and keeps it out of landfills. When purchasing plastic tools, make sure they contain a high proportion of recycled materials.
The use of pesticides is subject to increasing regulation in Canada because of the associated health risks. For the latest information, talk to a horticulturalist in person. You can also find information by referring to RONA’s pesticide policy.
Use appropriate gardening tools and avoid pesticides. Pesticides travel long distances, persist in the environment and accumulate in the food chain. They can be inhaled, absorbed through the skin or swallowed, and their impact on your health and the environment can be severe. Because children put their hands or other objects into their mouths, they are especially vulnerable to exposure, and their young bodies are highly sensitive to these products.
These noisy, polluting machines stir up dust that may contain bacteria, parasites and spores. Manual leaf collection methods save energy and have a smaller impact on your health.
Use a broom or rake rather than a leaf blower.
Natural fertilizers reduce resource use. They contain nitrogen, phosphorus and potassium, the three essential minerals for plant growth. The concentration of these natural fertilizers rarely exceeds 10% (for example 4-2-2 fertilizer, with 4% nitrogen, 2% phosphorus and 2% potassium). Be wary of so called “natural-based” or “organic-based” fertilizers, as they may contain as little as 15% natural products.
Natural fertilizers of organic origin come from animal waste (feather meal, bone meal, shrimp meal and dehydrated chicken waste) or plant waste (algae emulsion, corn gluten meal, alfalfa meal). The action of natural fertilizers on the soil is slower but more prolonged. They are also less susceptible to being washed away by precipitation, which protects waterways. Their persistence in the soil means they need only be applied twice a year, making them more economical despite their higher purchase cost.
Not mowing or reducing the size of the lawn gives you more latitude in your choice of mower. The main environmental impact to consider is the energy savings related to the mower’s use phase.
Silent, environmentally friendly push mowers are perfect for small spaces.
For larger areas, an electric or battery-operated mower is a good choice. These mowers emit no pollutants during operation. But remember: energy efficiency should still be considered, since the source of the electricity itself may be a source of atmospheric pollution (for example, coal- or oil-fired power stations). A gas mower with a 4-stroke engine is a better choice than one with a 2-stroke engine. Mowers equipped with a mulching function reduce the size of the clippings to accelerate their decomposition.
When it comes to insects, an ounce of prevention is worth a pound of cure. Most insects have favourite places to spend the winter and breed. By finding and eliminating these places, you can clamp down on their proliferation. Keep outdoor lights off in June and July, to avoid attracting June bugs, which are responsible for white grubs. Keeping your plants in good health will reduce aphid attacks, since they usually prey on weakened plants.
Use natural control methods. For example, sugar traps for wasps or crushed eggshells to ward off slugs. Ants don’t like damp conditions: mulching helps keep them away because mulch keeps moisture in the soil.
If natural methods don’t work, look for low-impact insecticides. They present less risk to your health and to the ecosystem. Insecticide soap, pyrethrin, diatomite, acetic acid, and iron phosphate are all healthier choices, but even these should be handled with care and used sparingly for “spot treatments.”
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