Government of New Brunswick

We share a complex eco-system with other living things, and the choices we make as consumers will impact in some way on the environment as a whole. Prevention is always the best solution for pests, weeds and plant disease in the yard and garden.

Today, more and more New Brunswickers are moving toward more environmentally friendly control methods and are learning more about peaceful co-existence with other creatures in our environment.

The New Brunswick Department of Environment oversees The Provincial Pesticides Control Act. For information about pesticide products, and proper application of pesticides, contact:

Bioscience and Resource Recovery Section
Stewardship Branch
P.O. Box 6000, Fredericton, NB E3B 5H1
Tel: (506) 453-7945 Fax: (506) 453-2390


Disease Control

Just like humans and animals, weak or stressed plants will suffer more than those that are strong and healthy. The gardener's long-term goal is to build up immunity to disease by improving the health of plants and soil. Many of the most common plant diseases can be prevented simply with good yard-care and gardening practices.

  • Choose disease-resistant varieties of plants that suit your conditions and climate. Carefully check new plants to be sure they are disease-free before you bring them into the garden.
  • Keep the soil healthy and well drained by digging in plenty of organic material, like compost.
  • Practice crop rotation. Change the locations of annual flowers and food crops from year to year.

Prevention is always the first step in disease control. The aim is to stop diseases from destroying an entire plant and diseased plants from infecting healthy ones.

Plant diseases are caused by fungi, bacteria or viruses, which thrive in damp or crowded gardens. They are often spread by insects, by touch, or by invisible spores carried on the wind.

Be on the safe side: clip off the affected part (or dig up the whole plant, if necessary), wrap it up well, and throw it in the garbage -- not in the compost pile. With soil-borne diseases like club root, dig up and dispose of the infected soil as well.

  • Sterilize garden tools and wash hands and/or change gloves after working with diseased plants, before going into a healthy area (in severe cases, some people advise changing clothes too).
  • Thin out crowded seedlings, pull weeds, and prune shrubs so fresh air can circulate freely.
  • Use drip-irrigation, soaker hoses or a watering can held close to the ground, rather than sprinkling plants from above. Water only when needed, and do it early in the day so leaves can dry completely before dew falls in the evening. Don't handle plants while their foliage is still wet -- in fact, try to stay out of the garden after it rains.
  • Snow mould, a light-grey fungus, affects many lawns in the wet weather of early spring: brush up the grass with an old broom as soon as you see signs of the fungi.

Solarization is a safe and long-lasting soil treatment, where the soil is covered with clear plastic during hot weather. The heat builds up in the top layers of earth, destroying disease organisms as well as many weed seeds and insect pests. Use this only in extreme cases, because earthworms and other garden helpers may be killed, too.


Start with a healthy soil, rich in organic matter. Plan the landscaping or garden to give your plants the kind of soil they prefer, and the amount of light and water they need to be strong and healthy. Make it easier for the plants to thrive.

  • Buy the best plants you can, and only from a reputable source.
  • Limit the number of weeds competing with young plants for nutrients in the soil.
  • Rotate garden crops each year, as different families of plants take different nutrients from the soil.
    Green lawns are the pride of our neighbourhoods, and it doesn't take chemical sprays to keep them looking lush and healthy.
  • Plant new grass on at least 6 inches of good topsoil.
  • Use a mixture of hardy grasses suited to our climate, and allow clover to remain in the lawn.
  • Cut the lawn regularly, so that grass clippings can stay where they fall, and top-dress each year by raking in a layer of fine compost. Most push mowers have stationary blade settings, designed to cut grass evenly, without cutting it too short which can weaken grass roots. A push mower is also an environmentally sensible choice because it doesn't require gas or electricity.
  • Water deeply and less often, rather than sprinkling, so the grass roots go down deep in search of moisture. A lawn with a strong root system can survive all sorts of hard use and bad weather.

Synthetic chemical fertilizers are advertised as a source of yard and garden miracles. Actually, they're more like junk food for plants than a sensible diet. Improperly used, these human-made fertilizers can actually increase the chance of disease and destroy the many beneficial insects that help the gardener with pest control and pollination. They can also make the soil too acidic, which means you spend more money on lime to correct that imbalance. Too much of a synthetic chemical fertilizer can even 'burn' the roots of growing plants.

Before adding specific nutrients or a concentrated fertilizer -- synthetic or organic -- test the soil to know what it really needs. Apply only what is required, in the recommended amounts.

  • Make your own compost, for a low-cost plant-food source that also supplies valuable organic material to the soil. You can never use too much compost!
  • Supplement your compost supply with bags of commercially prepared compost or manure from a reliable source.
  • Organic fertilizer products available to us commercially include blood meal, bone meal, rock phosphate, etc. Some reduce waste by making use of food industry by-products; others use natural mineral resources. While these fertilizers don't normally help soil structure the way compost will, used properly they can give plants a safe and steady source of nutrients.

Pest Control

Animals Pests

Animals come looking for food, for freshly turned earth, and for companionship. Deny the pests the things that attract them, and there's a better chance they'll leave your yard alone.

  • Keep meat, fats, and bones out of the compost. Wrap these things up well when you put out the household garbage, so the scent won't attract hungry meat-eaters. For the same reason, clean up carefully after a backyard barbecue or picnic.
  • Don't let your own pets run loose. If possible, train your own pet to stay out of forbidden areas of the property, spay or neuter outdoor pets, and keep unspayed females inside through mating season.

A fence may protect your yard and garden from unwanted animal visitors -- particularly dogs -- but there are no guarantees that the expense will be worth the results. Deer can often jump fences, cats and squirrels can climb them, mice ignore them, and groundhogs can tunnel underneath. Sometimes other measures are required.

  • Cover newly seeded garden beds with netting or chicken wire to discourage hungry birds and squirrels as well as digging cats.
  • To keep the bark from being stripped off tree trunks, wrap them with netting, chicken wire, or several layers of heavy paper.
  • Some people with lots of garden space plant extra seeds each year, so their families don't miss the part of the crop that goes to feed rabbits and raccoons.

Repellents trigger the natural fears and dislikes of animal pests, so it helps to be sure which animal is causing you problems. If you can't tell who's been eating the vegetables or digging in the flower bed, spread an even layer of ordinary white flour on the ground and watch for footprints. Once you know what animal is visiting, you can choose your tool for repelling it.

Bats, snakes, and toads aren't really pests at all, but some of the best natural allies we could have in the yard and garden. For example, one bat can eat thousands of mosquitoes each night, while toads love grubs, cutworms, slugs, and other insect pests. The harmless snakes native to New Brunswick help to control rodents and insects; garter snakes in particular are great for controlling slugs.

Birds are also welcome insect-eaters in the yard, but not when they take all the strawberries or make a meal of expensive grass seed where you hoped to have a lawn. Where netting isn't practical, try constructing a network of threads to discourage the birds from landing. Try to keep in mind that birds will always do more good than harm.

  • Provide fresh water and keep the birdfeeder filled, or plant "decoy" bushes of the sour berries birds prefer.
  • Scare off small birds with a statue of an owl, or cut the silhouette of a hawk from dark paper, cover it with plastic or some other weather resistant covering, and place it like a shadow in the garden. Lay out short lengths of an old garden hose to look like snakes.
  • Make shiny pinwheels from old foil pie plates, fastened to fence posts, or to sticks pushed into the ground. Hang milk cartons, crumpled foil, cardboard, styrofoam food trays, or other household discards in trees and change the display often.

Cats go for patches of soft earth more than what grows there -- unless it's catnip! Cover bare earth with chicken wire, stick a 'forest' of twigs and branches into the ground between young plants, or mulch with a coarse material such as shredded bark, pebbles, or wood chips. Avoid fish emulsion fertilizer, which attracts cats.

  • Try to catch digging cats "in the act" with a splash or spray of cold water: it won't hurt the cat, but he/she won't want to risk it too often. Remove any wastes and mask the lingering odour with a strong scent that cats don't like.

Deer can jump fences up to 6 to 8 feet high. Build a tall fence, or two lower fences (4 or 5 feet high and the same distance apart). Spread chicken wire on the ground where you can't otherwise close off your yard: deer don't like how it feels underfoot.

Dogs can be frustrating if you don't have a good strong fence. They cheerfully ignore most repellents, and walk right over chicken wire or netting covers.

  • If dogs are attracted to one particular shrub, perhaps on a corner of your property, try pounding a "decoy" stake into the ground, about a foot out from the drip line of the branches. A dog will often lift his/her leg against the stake, if it's closer, and won't damage the bush.

Groundhogs don't nibble, they devour. And they're tricky for the inexperienced person to trap successfully.

  • If a groundhog has already made a home on your property, be an annoying neighbour. Disturb its sensitive hearing with vibrations in the ground: pound a pipe deep into the ground near the tunnel and rig up pieces of metal or wood, like wind chimes, to hit the pipe almost constantly.

Mice and rats may go elsewhere to eat if grains in bird feeders are accessible only to birds, and other tempting food is kept in sealed garbage containers, and the yard is cleaned of anything that might serve as a nesting place.


  • If you have old plastic dropcloths or shower curtains, spread these between garden rows: raccoons, like many other animal pests, don't like to walk on plastic.
  • Some people plant just the outside rows of a corn patch with a later variety. With luck, the raccoons will be fooled into waiting for the late corn to ripen, and the gardener can enjoy the earlier crop.
  • Another tactic is to plant pumpkin or cucumber seeds between corn rows, because raccoons don't like to eat where they can't see, and these vines have a thick crop of large leaves.

Skunks are relatively harmless, not very intelligent, and great little night-hunters of rodents and insects. If a digging skunk leaves holes in your lawn, be pleased that it's hunting for harmful grubs: the holes will disappear in no time. Stay very still, when you meet a skunk, and let it wander away. Skunks spray only when they're startled or threatened -- tomato juice is still the best remedy for the smell.

Squirrels may cause havoc in bird feeders, but they don't do much other damage, except when they root up young plants while digging for something else. Flowering bulbs are an exception, often planted just when the squirrels are gathering a winter's supply of food: hide your tasty tulips bulbs among others that repel squirrels, like daffodils and the crown imperial fritillaria.

Insect Pests

Start the insect control program at ground level with the addition of organic material, like compost. Compost improves the soil, feeds the growing plants, and is free for the making. It also contains microscopic organisms that fight harmful insects -- without any help at all from us!

  • Keep lawns and gardens properly fed and well watered, and clean up around the yard periodically throughout the growing season.
  • Practice crop rotation, changing the locations of annual flowers and food crops from year to year.
  • Carefully check that any new plants you bring in are insect-free.
  • Look for signs of disease in the garden. Sick plants seem to attract insect pests and are less likely to survive than strong, healthy plants.
  • A little research will help you learn to time plantings so that harmful insects are at their least active stage when the plants are most susceptible to damage.
  • Because many unwanted bugs hide or lay eggs just beneath the surface of the soil, disturb the ground with a hoe or cultivator tool to shake them up.

The key to insect control is management, not destruction. Hand-pick insects and their egg masses from plants, if you aren't too squeamish, looking particularly for those hiding on the under-side of leaves. A night-time search with a flashlight will turn up slugs and other pests which hide from sunlight. Squish them, or drown them in soapy water. If you don't want to get so close to your victims, you can blast them off the plants with a strong spray of water. Physical barriers and traps are also safe and effective:

  • Cover garden crops with row covers or lengths of cheesecloth, or use stem collars and mulches to keep pests from getting to your plants.
  • Spread a sticky substance (check with your garden centre) in a band around tree trunks before caterpillars, like the detested 'army worm, or tent caterpillar', climb up to build their nests. 
  • Catch flying insects with yellow sticky traps, which work much like old-fashioned fly-paper. 
  • Shallow saucers or jar lids of a fermenting liquid -- like beer, yeast and water, or spoiled yoghurt -- will attract and drown slugs and many beetles.
  • You can also buy specialized traps that use sex pheromones to attract one particular type of insect. With these traps, you can be assured that beneficial insects aren't caught by accident.

Be aware that light traps, the blacklights that attract and 'zap' insects, may actually make an insect problem worse in the long term, because they kill a great many beneficial insects as well as some of the pests. And they don't seem to be very effective against the bugs that bite us.

It's easier to deal calmly with garden insects when human-biting insects back off. Drain any standing water that offers a breeding ground for mosquitoes, and cover up with loose, light-coloured clothing in mosquito and black-fly season.

Nature offers a lot of help for pest management-- birds, bats, snakes, toads, and even other insects. In fact, most of the insects that inhabit our yards and gardens are either harmless or actually helpful. That's why it's not wise to spray poison at every bug you see.

Ask landscape professionals for information on identifying and encouraging beneficial insects, or check any good modern book on organic gardening. You can grow a host of attractive plants which serve as homes to the 'good bugs' who prey on the pests -- or buy the very insects you need to fight specific problems (although there's no guarantee that imported bugs will stay in your yard).

Other natural controls include 'germ warfare' for the home gardener. Selective disease organisms like Bacillus thuringiensis, often called Bt, are available commercially and affect only a small group of insects.

As noted earlier, solarization is a safe soil treatment for bad infestations, and the effects can last for several years. Cover the unplanted garden bed with clear plastic during hot weather: enough heat will build up to destroy soil-living pests as well as disease organisms and weed seeds. Do this cautiously, because earthworms and other garden helpers may be killed, too.

Garden centres carry a wide selection of dusts and sprays. If you decide to use a pesticide, ensure that it is a registered product, choose the product with care and handle it with cautious respect. Use as little as possible, and always follow label instructions. Insect pests may build up a resistance to a pesticide, while repeated exposure increases the risks to humans, pets, wildlife and beneficial insects. Over-used, pesticides may even harm the plants they're intended to protect.

For more information on pest control options, contact the Stewardship Branch of the Department of Environment, (506) 453-7945. For more information on indoor pest management, see the section labeled "Insect Pest Treatments" in this guide.


Weed Control

Weeds compete with the plants you want to grow for available food, water, and sunlight. A few are poisonous; others may shelter insect pests or contribute to the spread of plant diseases. Some weeds seem almost impossible to destroy, once they take hold in the lawn or garden.

Consult gardening books to identify your weeds. If you know what you're fighting, you can plan a strategy to match. By far, most of our weeds are annuals, which live one season, set seed, and die. The remainder are perennials or biennials, which come back again next year and spread by sprouting from their roots as well as by setting seed.

A small investment in time and energy will keep existing weeds from getting out of control. As always, prevention is the first line of defense: stop the weeds before they get started.

  • Some common weeds, like plantain, grow best in poor-quality, compacted ground. Frustrate these by loosening the soil to let air in at root level. Aerate lawns, and dig lots of compost into gardens.
  • Cut lawns no shorter than 2 1/2 or 3 inches, to keep the grass strong, but mow frequently so weeds won't have a chance to form seeds. For best results, use a push mower.
  • Lay a landscape fabric under the soil of permanent flowerbeds for long-term weed control.
  • Cover exposed earth and pathways with a mulch so that weed seeds can't take hold.
  • Smother out perennial weeds with a heavy layer of mulch left on for the full growing season.
  • Hand-pull weeds before they can go to seed, or chop them off just below the soil's surface with a sharp hoe. Get them while they're young and weak.
  • Pour boiling water carefully on those weeds that show up in a path or driveway -- where you don't want anything to grow. On those monster weeds that can push up through asphalt, aim for the place where the stem meets the ground. For stubborn perennial weeds, where tiny parts of roots can re-sprout, you will want to repeat the treatment every couple of weeks to progressively weaken the plant. It's a safe, cheap solution that really works.
  • Reclaim larger areas of weed-covered ground with solarization, where summer heat is trapped beneath clear plastic to 'pasteurize' the soil. Note: Remember that solarization, especially over a prolonged period, can also harm or kill important soil aerators like earthworms.

Each season of good gardening means fewer weeds the next year. Some research suggests that the occasional weed is a good thing, giving a home to beneficial insects and in some mysterious way contributing to the health of other plants. It's all part of maintaining a balance in the complex eco-system of your own back yard.

For more information on Integrated Pest Management, contact:

The Stewardship Branch
Dept. of Environment
P.O. Box 6000
Fredericton, NB E3B 5H1
Tel: (506) 453-7945
Fax: (506) 453-2390