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Gardening … all naturally

2016 Edition

Be tolerant!

Why panic at the sight of a few undesirable insects or plants? Learn to tolerate their presence if they cause little damage. It is simply a question of common sense.

The presence of a few “undesirables” doesn’t at all mean that you will inevitably be victimized by an infestation. Using a few simple tricks, you will have no trouble maintaining the number of pests at an acceptable level. And, more often than not, natural predators already on the scene, such as birds and certain insects, will also help you out. The same applies to certain plants, that some consider harmful, and others, beneficial. Biodiversity is your best bet!

Useful organisms: allies to be protected

Pesticides can eliminate or affect useful organisms. These latter allies play a beneficial role by improving surroundings, pollinating plants, and preying on undesirable organisms or parasitizing them.

Remember, when you kill an ally, you create more work for yourself. Avoid the use of pesticides to protect these useful organisms and encourage their presence.

Allies to protect

Principal roles

  • They are untiring natural soil aerators.
  • They transform organic matter in the soil.
  • The adults devour more than 50 aphids per day and larvae can devour over 150 a day.
  • Asian ladybugs are also useful. However, they cannot withstand our harsh winters and invade homes in cold weather.

To learn more about Asian ladybugs and on how to prevent them from getting inside, go to:

  • They eat aphids, scale insects and plant bug larvae.
Parasitoid insects (wasps, etc.)
  • They develop on or inside another insect, drawing on its food, and finally, upon reaching maturity, kill it.
Bees and other pollinator insects (bumble bees, etc.)
  • They pollinate the flowers of trees and garden plants, which produce fruit and vegetables.
Flower flies
  • The adults are good pollinators.
  • The larvae feed on aphids and the larvae of several insects.
SpidersDragonflies – Insectivorous birds (swallows, chickadees, etc.)
  • They prey on insects and larvae.
  • These nocturnal animals eat slugs, earwigs and other insects.
Millipedes – Centipedes – Sow bugs – Ground beetles
  • They decompose organic matter.
  • They cause little damage to plants.
  • Active at night, ground beetles prey on large quantities of caterpillars and slugs.


What to plant to attract useful insects?

As well as feeding on other insects and water, certain useful insects consume pollen and nectar. Why not introduce plants in your garden and flower beds that mass produce both?

Plants of the mint family (Lamiacea):

  • Lemon balm (Melissa officinalis)
  • Wild thyme (Thymus serpyllum)
  • Spearmint (Mentha spicata)
  • Russian sage (Perovskia atriplicifolia)
  • Bee-balm (Monarda didyma)
Plants of the carrot family (Apiacea)
  • Dill (Anethum graveolens)
  • Fennel (Foeniculum vulgare)
  • Caraway (Carum carvi)
  • Coriander (Coriandrum sativum)

Plants of the daisy family (Asteracea)

  • Cosmos (Cosmos bipannitus)
  • Cornflower (Centaurea cyanus)
  • Perennial rudbeckia (Rudbeckia fulgida)
  • Achillea (Achillea millefolium)
Lures and useful insects
A number of garden centers can provide useful insects for your garden, flower beds and/or houseplants. Lures for attracting useful insects to your garden are also available on the market: they act as a pantry (offering pollen, nectar and various proteins) or give off the odour of a prey (of an aphid, for example). If your garden center doesn’t have any in stock, ask that they put in an order.

How best to prepare and maintain what you plant


Click to enlarge (French)

Your garden

In order for your garden to flourish, you have to get off to a good start. How? Well, before planting, you should prepare a garden plan; for instance you might draw up a layout, taking into account the special needs of each plant and the sort of environment in which you want to plant it.

Here are your main rules of thumb:

  • Make sure the soil is fertile and well drained;
  • Do yearly digging to aerate the soil and make it less compact;
  • Do frequent weeding and hoeing;
  • Water the soil and not the leaves and do so in the morning if you can (try to set up a “drip-style” sprinkler so as to avoid fungus-related diseases);
  • Promote species diversity;
  • Make sure that your garden gets at least 6 hours of daily sun;
  • Whenever possible, do companion planting;
  • Make sure to carry out a yearly plant rotation; and
  • In fall, remove all left over vegetables and plant debris, thus reducing the risk of infestation in the upcoming year: undesirable disease-causing insects and fungi may hibernate in these remnants.

Flower beds, trees and shrubs

A crucial stage in flower bed planning involves drafting a plan or general layout since you can find a vast array of plants with all sorts of special needs (hardiness, sunshine, soil richness, dampness, etc.). Choose plants that are adapted to the conditions of your site. The rules of thumb for your garden (fertile soil, rotation, weeding, etc.) apply to your flower beds as well. And mycorrhizal fungi, a growth stimulant, can be incorporated into the soil.

Your lawn

  • Soil preparation prior to sowing or sodding is the first point to consider. A layer of rich soil at least 15 cm thick is necessary for healthy grass.
  • In spring or late summer resow bare spots or places where growth is sparse to prevent these areas from being invaded by weeds. Promote biodiversity in your lawn.For example, add white clover to your grass seed mixture. White clover resists foot traffic and dry spells. Unlike grass, it is able to capture atmospheric nitrogen, thereby reducing the need for fertilizer. In the shade, introduce ground-cover; such plants are better suited to these conditions.
  • Maintain soil fertility. Learn to identify weeds since their presence is an indicator of soil health (dandelions are an indication of poor soil, hawkweed is an indicator of acidic conditions, etc.).
    • Maintain a soil pH level of between 6 and 7 to ensure optimum uptake of nutrients (nitrogen, phosphorous, potassium, magnesium, calcium, etc.). If necessary, compensate for acidic soil (pH < 6) by applying dolomitic lime in the fall.
    • Apply a top dressing compost to your lawn after aeration to promote the activity of microorganisms in the soil. Top dressing consists of uniformly spreading 0.5 kg of compost per square metre in the spring and using a leaf rake to filter it through the lawn to soil level.
    • Fertilize in the spring, and in the fall fertilize again if you applied only half the fertilizer dose early in the season.
    • Leave grass clippings on the lawn if you cut less than one third the total height of grass at a time. If you can, use a mulching mower, which finely grinds clippings and accelerates decomposition. Grass clippings can supply up to 30 percent of a lawn’s fertilizer needs.

Choose a natural fertilizer

A fertilizer is a substance, or a mixture of substances, containing nitrogen, phosphorus, potassium and any other plant nutrient. Nitrogen, phosphorus and potassium are essential to plant growth and development and their respective percentages in the fertilizer is indicated on packaging.

Natural fertilizers can be organic (animal or plant residue) or mineral (stone powder). These fertilizers have not been altered chemically. Unlike most synthetic or chemical fertilizers, natural fertilizers need to be broken down by organisms living in the soil in order for their nutrients to be released. Therefore, in addition to feeding plants, natural fertilizers contribute to soil life.

  • Practice good mowing techniques.
    • Cut lawns to a height of 6 to 8 cm during the summer. The first and last cut of the season can be 5 cm. The shorter the lawn, the more vulnerable it is to weeds.
    • Regularly change the direction of cutting to reduce the accumulation of clippings.
    • Sharpen mower blades, ideally after every 8 hours of use, for a clean cut. Grass blades that are torn are more vulnerable to disease.

Weeds and mowing height

Click to enlarge (French) - Weeds and mowing height

Lawn maintenance and mowing height

Click to enlarge (French)  - Lawn maintenance and mowing height

Click to enlarge (French)

Click to enlarge (French)

You want to learn more about lawn maintenance?

Alternatives to lawns along lakes and watercourses

Leave a strip of natural vegetation (trees and shrubs, indigenous ground-cover plants, uncut herbaceous plants, etc.) along the edges of lakes, rivers and streams revegetate the shoreline. Ideally this strip – which should be wider when the slope is steeper – is never treated with fertilizer. Fertilizer must not be applied within 3 metres of lakes or watercourses.

This wise approach makes it possible to save lakes and watercourses and to preserve and showcase our fauna and their habitat.

Control lawn watering

In Québec, drinking water consumption doubles in the summer. Watering lawns, flowerbeds and gardens is at the root of such overuse. A water hose at full throttle dispenses 1000 litres of water per hour, the equivalent of the recommended water consumption quantity for one person over 18 months.

Contrary to a popular concept, lawns do not need large amounts of water. Indeed, over half of the water consumed is lost through evaporation or surface runoff.

  • Water early in the morning – as soon as the dew has evaporated – or in late afternoon. This will minimize water loss due to evaporation. After a heavy downpour, no watering is required for a week or more. Obviously, respect municipal water restrictions.
  • Water your lawn when the soil is dry at root level. If this is the case, water less often, but deeper (2 to 3 cm of water per watering at ground level) to improve deeper plant rooting. Place similar-sized containers around the lawn in a few locations; stop watering when the recommended amount of water has accumulated in the containers.
  • If a lawn turns yellow during a dry spell, do not water or mow. The grass is dormant, and growth will resume after a rainfall and when weather conditions return to normal.
  • Mow your lawn to a height of 6 to 8 cm to encourage deep root growth and make grass more drought-resistant.
  • In the spring, insert a screwdriver to a depth of 15 cm in several locations around the lawn; if you feel any resistance, aerate the soil mechanically by extracting small soil plugs. This practice allows water to seep into soil, improves gas exchanges and allows roots to spread.


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