My Cart


Rebecca Small - May 31 2020

Dealing with Garden Pests and Problems

Mome June, chances are you’ve got the bulk of your plant shopping done, your containers filled with colourful annuals and your perennial beds coming into their full glory. Focus now shifts from acquiring new plants to keeping the ones you have healthy and living up to their full potential. One factor that stops your outdoor plants from looking their best is pests and insects. They chew holes in leaves, suck juices from tender stems and can wreak havoc on your lawn. Here are Parkway’s top tips to identify and treat common pests and problems!

Deer and Rabbits

Hungry deer and rabbits can be a major nuisance in a garden. Because of their size they can quickly do a large amount of damage. While you may never actually catch them in the act they can strip bark and leaves from trees and shrubs and nibble perennials right to the ground. 

Protect young and slender trees from bark stripping with a plastic trunk wrap or corrugated big O plastic pipe wrapped around the trunk of the tree. This will prevent deer and rabbits from chewing the bark, especially in colder months when food is limited. Discourage critters from eating your plants with Bobbex Deer and Rabbit Repellent. This safe repellent spray will naturally discourage deer, rabbits, squirrels, groundhogs, chipmunks and voles. 

Powdery Mildew

 This fungus will appear as white or grey powdery blotches on a plant’s leaves. It is often found on roses, tall phlox, bee balm, ninebark and lilac shrubs. It thrives in warm, moist conditions.

Water your plant by saturating the soil, not showering the whole plant, as water left to sit on the leaves will increase the problem. Do your watering in the morning so your plant can use it throughout the day. Evening watering will leave your plant with extra moisture and humidity that can increase mildew. Trim off any leaves with signs of mildew and throw them in the garbage, not the compost, as this can allow the infection to spread. Don’t let any of the plant’s fallen leaves hang around in your garden. Carefully trim out some of the inner branches and stems to increase airflow around the leaves which will reduce excess moisture. Finally, treat your plant using Safer's Garden Defender Fungicide or Safer’s Sulphur Dust. These products treat powdery mildew, rust and black spot as well. 


Aphids come in a variety of colours, including black, bright green and orange. They can often be found in clusters on young stems and leaves and damage your plant by sucking out it’s juices with their piercing mouths, causing leaves to become distorted and damaged. They can be identified by two tiny ‘tail pipes’ on their back end. They are often found on roses, burning bushes, coral bells and milkweed. 

While aphids can be easily dislodged by a stream of water from the hose they will likely come back. To eliminate them use Safer’s Insecticidal Soap. Spray it directly on the aphids and it will weaken their outer shell, causing them to dehydrate and die. It may take a second application to completely eliminate them. 


Grubs are the young larva of beetles. In Ontario the main species we deal with are June Beetles, European Chafers, and Japanese Beetles. They live underground and feed on the roots of plants, predominantly grass roots. The problem can be identified by dead, brown patches of lawn where roots have already been damaged and spongy ground with turf that is easy to pull up. Grubs also attract racoons and skunks which will dig up your lawn to feast on the underground grubs. 

Nematodes are microscopic beneficial insects that kill grubs. Nematodes should be applied in spring and fall as long as temperatures are above 10 degrees celsius. Depending on the preparation of nematodes they can be mixed with water and applied with a watering can or hose end sprayer or a dry mixture that can be spread over the lawn using a fertilizer spreader. Use Lawn Guardian Nematodes for a water application and Scott’s Grub BGon Max for dry application. Lawn Guardian Nematodes and many other brands need to be refrigerated until use so be sure to read the package and follow the directions. 

Japanese Beetles

Japanese Beetles seem to descend in hoards every July and can quickly do a lot of damage by chewing leaves and defoliating plants. Some of their favourite meals include Japanese maples, roses, perennial hibiscus and hollyhocks. 

Apply nematodes in the spring and fall to kill Japanese beetles in their larval stage. If you’ve missed your opportunity and adult beetles are already present you can use a pheromone trap. Pheromones attract japanese beetles which are then trapped in a plastic bag and unable to fly or climb back out. Make sure you set up the trap as far as possible from the plants you want to protect. Some gardeners swear by the use of common annual geraniums to repel Japanese beetles. While this is not a sure fire method, you may consider planting them in your garden as an added measure. When all else fails and you must get rid of Japanese beetles, the last resort is hand picking. Wear a thick pair of gloves to remove beetles from plants (sometimes by the handful) and quickly toss them into a bucket of soapy water.

Pests can pose many challenges for gardeners but there are many solutions to minimize damage to your garden. Be vigilant in monitoring your plants so you can treat problems early for best results.