Brochures

Plant Problems

Pest Control Alternatives

Many city dwellers expect instant solutions when it comes to controlling insects and weeds in their gardens and back yards; simply spray a pesticide and the problem is solved.  Unfortunately, it’s not as simple as that.  Many pest control products are poisonous; otherwise they would not be effective controls.

Like any poison around the home, pesticides should be used as a last resort and with extreme caution.  Have you ever stopped to consider that some pest problems may not need to be treated with a pest control product?  On the small scale of yard and family gardens, nonchemical pest control can be a feasible alternative.

Why Try Alternative Pest Control?

Pest control products are toxic to many forms of life in addition to the species controlled.  Honeybees and useful predatory insects such as ladybugs can be killed outright when the pest control product is applied.  Pest control product residues can accumulate in the food chain causing damage to birds, fish and other forms of animal life.  In many cases these side effects are not immediately apparent, but show up later; for example, in the abnormal eggs laid by birds that have fed on insects that have been sprayed.  Ultimately some side effects may extend to human life as well.

Using a pest control product can be compared to taking a prescription drug, in that the benefits must be weighed against the side effects.  Pest control products alleviate symptoms, but do not provide a cure: they have not eliminated one insect species from the planet.  In fact, extensive use of pest control products in agriculture has led to the development of genetically resistant insect and weed species that are no longer affected by some commonly used pest control products. 

Alternative Methods of Pest Control

Trees and Shrubs

In the majority of cases, damage by insects is more troubling to the homeowner than it is to the plant.  Most trees and shrubs can survive pest infestations.  
Here are some ways to control pests without resorting to a chemical based pest control product:

  • pick off infested leaves by hand and dispose of them.  This will control moderate infestations of some pests like—lilac leaf miner, leaf rollers and spruce budworm larvae.
  • in late fall or early spring, prune off branches containing the graying egg bands of the forest tent caterpillar.  Use a knife to scrape the egg bands off the larger limbs.
  • if forest tent caterpillar eggs have hatched pick off larvae by hand when the cluster together in late evening or on cool days.
  • using a garden hose, direct a strong stream of water against trees and shrubs to dislodge insects.  This is effective against spider mites and pear slugs as well as other pests.
  • make your own safe insecticide by adding 30ml (2tbsp) of soap flakes to a liter of water and dousing infected leaves.  Use ordinary soap flakes (not laundry detergent) or an insecticidal soap and apply the solution with a watering can. 
  • if a pest control product in needed, try an organic insecticidal soap or pyrethrum.  Pyrethrum is a natural substance derived from flowers of the chrysanthemum family.
Lawns
  • 2,4-D and related compounds are commonly used to rid lawns of dandelions and thistles.  These compounds are biological poisons and remain on the lawn for a number of weeks.
  • whenever possible, dig out weeds by hand
  • keep your lawn well watered and fertilized.  A healthy lawn is a very effective deterrent for weeds.
Vegetable Gardens
  • Pick off infested leaves by hand to control insects such as Colorado potato beetle.
  • To keep cutworms away from tomatoes, peas, cabbage and beans remove both ends from a tin cans and sink them around the plants.
  • place tar covered paper around the base of cabbage plants to prevent cabbage flies from laying eggs.
  • scatter onions throughout the garden instead of planting them in rows so root maggots can’t simply travel from plant to plant.
  • rotate crops each year to prevent soil from being depleted of nutrients and to control soil-born diseases.
  • use a soap flake solution (see trees and shrubs) to dislodge or suffocate insects.
  • cultivate your garden.  Regular hoeing will control weeds and keep plants healthy and more resistant insect attacks.
Companion Planting
  • Vegetables and flowers have different scents and root secretions that are believed to affect the activity of insects and the growth of nearby plants.
  • plant marigolds and other members of the chrysanthemum family throughout the garden to protect tomatoes, beans and other plants from a variety of insects.
  • sow aromatic plants at intervals throughout the garden to ward off pests.  Chives, dill, nasturtiums, geraniums, thyme, basil, celery, mint, garlic and onions are examples of aromatic plants often grown for their own value anyway.
  • basil is said to keep tomatoes free from infestations and savory to protect beans.  Onions or garlic sowed next to carrots will foil the carrot fly.
  • plant horseradish at the corners of a potato patch and plant beans near potatoes to repel the Colorado potato beetle. 

Conclusion

Remember that pest control products only relive symptoms they are not a cure-all.  Insects will never be eradicated. Minor pest damage should be expected and to an extent, tolerated.   Think of your yard and garden as a small portion of nature in which pests have their place.  Often nature provides its own pest control in the form of birds and other insects that feed on the species we consider nuisances.

Keeping your plants healthy and happy will help discourage pest attacks.  Pest attacks are going to happen, so become more    tolerant to minor pest damage! 

Cited: Alternative to Pesticides, Environment Canada.