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Gardening … the all-natural way

2019 Edition


Be tolerant!

Why panic when you see the odd undesirable insect or plant? Learn to tolerate them if they cause little damage. It's simply a question of common sense.

A few “undesirables” in your garden will not inevitably turn into an infestation. A few simple tricks will make it easy to keep the number of pests at an acceptable level. And, more often than not, natural predators, such as birds and other insects, will help you out. The same applies to plants that some consider harmful while others see them as beneficial. Biodiversity is your best bet!

Useful organisms: Protect your allies

Pesticides can eliminate or damage useful organisms that are your allies and that have a beneficial role to play by improving your environment, pollinating plants, and preying on or parasitizing undesirable organisms.

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

Protect your allies

Principal roles and functions

Earthworms
  • Untiring natural soil aerators
  • Transform organic matter in the soil
Ladybugs (also called Lady Beetles)
  • Adults eat more than 50 aphids per day while the 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 how to prevent them from getting inside your home, go to:

Lacewings
  • Eat aphids, scale insects and plant bug larvae
Parasitic insects (wasps, etc.)
  • Develop on or inside another insect, drawing on its food, and finally, upon reaching maturity, kill it
Bees and other pollinating
  • Pollinate the flowers of trees and garden plants that produce fruit and vegetables
Flower flies
  • Adults are good pollinators
  • Larvae feed on aphids and the larvae of other insects
SpidersDragonflies–Insectivorous birds (swallows, chickadees, etc.)
  • Prey on insects and larvae
Toads
  • Nocturnal animals - eat slugs, earwigs and other insects
Millipedes–Centipedes–Sow bugs–Ground beetles
  • Decompose organic matter
  • Cause little damage to plants
  • Active at night, ground beetles prey on large quantities of caterpillars and slugs

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What should you plant to attract useful insects?

As well as feeding on other insects and drinking water, some useful insects consume pollen and nectar. Why not attract them by introducing plants into 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
Some garden centres sell useful insects for your garden, flower beds and/or houseplants. Lures for attracting useful insects to your garden are also available: they act as a pantry (offering pollen, nectar and various proteins) or give off the odour of prey such as an aphid. If your garden centre doesn’t stock them, you can put in a special order.

How best to prepare and care for what you plant

FAVOURABLE CONDITIONS FOR YOUR PLANTS
Click to enlarge (French) - FAVOURABLE CONDITIONS FOR YOUR PLANTS

Click to enlarge (French)

Your garden

Getting off to a good start will help your garden to flourish. Before you plant, prepare a vegetable garden plan. For instance you might draft a layout, taking into account the special needs of each plant and the kind 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
  • Turn over the soil each year to aerate and decompact it
  • Weed and hoe frequently
  • Water the soil in the morning if possible, not the leaves. Drip sprinklers can stave off fungus-related plant diseases
  • Promote species diversity
  • Make sure that your garden gets at least 6 hours of sun daily
  • Whenever possible, practice companion planting
  • Carry out yearly plant rotation
  • In fall, remove all left over vegetables and plant debris. This will reduce the danger of infestation in the following year. Undesirable disease-causing insects and fungi can hibernate in these remnants

Flower beds, trees and shrubs

A crucial stage in flower bed planning involves drafting a plan or general layout since a vast array of plants can be found, each with its own special needs (hardiness, sunshine, type and richness of soil, 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 can be added to the soil to stimulate growth.

Your lawn

  • Soil preparation prior to sowing or sodding is the first point to consider. A layer of rich soil at least 15 cm in thickness is necessary for healthy grass.
  • In spring or late summer, sow bare spots or places where growth is sparse to prevent weed invasion. 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 can capture atmospheric nitrogen, thereby reducing the need for fertilizer. In shady areas, use ground-cover plants that are better suited to these conditions.
  • Maintain soil fertility. Learn to identify weeds since they are good indicators of soil health (dandelions are an indication of poor soil, hawkweed is an indicator of acidic soil, etc.).
    • Maintain soil pH level of between 6 and 7 to ensure optimum uptake of nutrients like nitrogen, phosphorous, potassium, magnesium, and calcium. If necessary, compensate for acidic soil (pH < 6) by applying dolomitic lime in the fall.
    • Apply top dressing compost to your lawn after aeration to promote microorganism soil activity. 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 the soil level.
    • Fertilize in spring, and again in fall 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 are shown on the packaging.

Natural fertilizers can be organic (animal or plant residues) 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 that live in the soil in order for their nutrients to be released. This means that, in addition to feeding plants, natural fertilizers contribute to healthy soil life.

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

Would you like to learn more about lawn maintenance? Click on

Alternatives to lawns along lakes, rivers and streams

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 to vegetate the shoreline. Ideally this strip–which should be wider when slope is steeper–should never be treated with fertilizer. Fertilizer must not be applied within 3 metres bodies of water.

This wise approach helps save our lakes and watercourses and preserve and showcase wildlife.

Lawn watering control

In Québec, drinking water consumption doubles in the summer. Lawns, flowerbed and garden watering is at the root of this resource overuse. A hose at full throttle spews out 1000 litres of water per hour, which is the equivalent of the recommended water consumption for one person over 18 months.

Contrary to popular belief, lawns do not require large amounts of water to thrive. Indeed, over half of the water applied to lawns 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 from evaporation. After a heavy downpour, no watering is required for at least a week. Obviously, abide by municipal water usage 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 in depth per watering at ground level) to improve plant rooting. Place similar-sized containers around the lawn in several locations and stop watering when the recommended amount of water has accumulated in them.
  • 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 resistance, aerate the soil mechanically by withdrawing small soil plugs. This practice allows water to seep into soil, improves gas exchange and enables roots to spread.

 


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