Insects are a natural part of any garden. Most insects are beneficial, but some are not desirable and can cause harm to your flowers and vegetables. Using pesticides and herbicides will usually kill all insects, not just the harmful ones and these chemicals are poisons that can be harmful to people and animals. It is impossible to completely rid any garden of all insects, but there are natural methods that you can use to control the harmful ones. Here are some suggestions of some methods that you may try:
The first line of defence against bugs is to simply pick them off. Squish the bugs as you pick them off. If you find a large number of bugs on one crop it is often easier to pick and drop into a container of soap and water. Simply dispose of the dead bugs after they have drowned. This is an effective method for many insects like potato beetles and aphids.
If you encounter a nest or gall of insects before it hatches it is easy to cut it off. This must be done in a timely matter before the insects hatch and leave the nest. Be sure to destroy the nest or gall so that the insects cannot spread after they have been removed. The tent caterpillar is an example of a pest that can be controlled using this method.
Spraying with Water
Small insects can be washed away with a stream of cool water. The spray will dislodge and wash away some of the bugs, reducing their numbers and the amount of damage they can do. Because spraying will not remove 100% of the bugs, you will have to repeat every few days. Aphids are an example of insects that can be managed in this way.
Some plants have a history of being susceptible to damage by insects. By using transplants rather than directly seeding, the plants may have a better chance of surviving. Even if the bugs eat the same amount, if the plant is larger it will be able to handle the stress better. The larger the plant, the more leaves it will be able to handle losing.
Keep Things Clean
Be sure to continually clean up your garden throughout the season. In the fall it is especially important to clean up old plant matter. Some insects can overwinter in leaf litter. If you’ve had problems with one plant in particular, be sure to burn or throw out leaves, cuttings, et cetera, instead of putting them in the compost.
Tree bands covered with a sticky substance can catch wingless insects, such as caterpillars, before they lay eggs in the tree. These also catch beneficial insects. Tree bands should only be applied between September to May.
Physical barriers placed around and on plants can prevent insects from eating vegetables, spreading disease, and from laying their eggs on plants. You can buy commercial covers or create your own at home from netting or pantyhose. Collars placed in the dirt can prevent cutworm damage. Tarps laid around fruit trees can prevent larvae on fruit from entering the soil. Although some of these methods can be unsightly they are often very effective.
Insecticidal soaps are effective against small, soft-bodied insects, but have low toxicity to mammals and do not often harm larger, flying insects such as bees. To be effective, the soap must come in contact with the insect. Some plants may be sensitive to insecticidal soaps. Therefore, it is a good idea to test a small area on a plant if you are not sure. Visit your local garden centre to see what products are available in your area.
Predator insects are insects that naturally eat the undesirable ones. Some of these are native to Manitoba and some can be introduced. The most well-known predator insect is probably the ladybug. These are found naturally in Manitoba and can also be purchased at your local garden centre. Ladybugs only eat aphids. The downside of using lady beetles is that they may fly away. Another predator insect that can be purchased is the praying mantis. The mantis has a voracious appetite and it is territorial. If there is enough food for it, the mantis will usually not wander far from where it hatched.
These are just some of the natural insect control practices that are used today. Visit our garden store to see what products and methods our experts suggest.