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Safe and Effective Pest and Disease Remedies




Bt / Btk exists naturally in most soils. Different strains of Bt / Btk occur that produce protein crystals toxic to certain insects. The strain for most caterpillars is B.t. var. kurstaki. Commercially prepared Bt spray or powder has no effect on adult butterflies or moths. Remember, however, that not all caterpillars are pests.

Strains of Bt / Btk have been developed for a few other pests. Some Leaf-feeding beetles are susceptible to B.t. tenebrionis, for example.

Advantages :
Bt is essentially non-toxic to humans, other mammals and birds. The label specifies that not waiting period between application and harvest. Bt / Btk is also highly selective and so easily incorporated with existing natural controls.
Disadvantages :
Somewhat slow action. After pests consume it, their feeding slows down, but their death may not occur for two to five days. Bt / Btk also breaks down quickly, so if the caterpillars don't eat it while it is fresh, it likely won't work.

Because Bt /Btk is a near perfect insecticide, there is danger of overuse. Any overuse of an insecticide gradually becomes less effective as insects evolve defenses to it. Some insect pests that were once susceptible are now at least partially immune to it.

How to use :
Use Bt / Btk against cabbageworms, tomato hornworm, tent caterpillar, gypsy moth, leafrollers, cutworms, and other caterpillars on vegetables, fruits, shade trees, ornamentals and evergreens. Use B.t. tenebrionis against Colorado Potato Beetle. The bacterial toxin causes caterpillar death two to five days after it is eaten, the toxic dissipates in two days or less. It is available as a liquid spray or a dust. Apply in the late afternoon and re-apply after rain. Repeat applications as needed. Mix with insecticidal soap for greater effectiveness.

Diatomaceous Earth

Diatomaceous Earth is a powder like dust made of the silicated skeletons of tiny marine creatures called diatoms. Millions of years ago, as they died, their skeletons gradually accumulated into deep layers that are mined today from deposits where oceans or large lakes once covered the land. Diatomaceous Earth acts like ground glass, cutting into the waxy coats of insects and causing them to dry out and die.

Advantages :
It is not toxic if eaten, but it is irritating if inhaled.
Disadvantages :
It is not selective and kills spiders and beneficial insects as well as the pests.

Diatomaceous Earth is available in two forms. One, which is used primarily in swimming pool filters, is not an effective insecticide and is dangerous to inhale. (Can cause a lung disease called silicosis) In your garden use only the natural grade of Diatomaceous Earth. Still, it is best to wear goggles and a dust mask during application.

Horticultural Oils

Horticultural Oils are most often highly refined extracts of crude oil. (Some vegetable oils, such as cottonseed or soybean, are also sometimes used.) They kill insects by plugging the pores through which the insect breathes.

Advantages :
These oils are increasingly recommended for vegetable garden pest control because they pose few risks to either gardeners or desirable species and integrate well with natural biological controls. Also, oils dissipate quickly through evaporation, leaving little residue.
Disadvantages :
Oils can damage plants if applied at excessive rates or on particularly hot (more than 100F/37C) or cold (less than 40F/4C) days.
How to Use :
Spray oils in vegetable gardens to kill aphids, leafhopper, spider mites, caterpillars, leafrollers, scale and whiteflies. When mixed with a small amount of baking soda, it is also an effective control for powdery mildew. A few drops of oil in the ear tips of corn will control corn earworm. Use highly refined Horticultural Oils and dilute according to label directions. Do not apply oils to drought-stressed plants, or on very hot or very cold or very humid days. Do not apply Horticultural Oils to green plants at rates recommended for leafless, dormant plants. Plants that tend to be sensitive to Horticultural Oils are black walnut, douglas fir, hickories, junipers, cedars, maples (particularly Japanese and red maple), red bud, smoke tree and spruce (particularly dwarf Alberta spruce).

Insecticidal Soap

Insecticidal Soaps are specific fatty acids that have been found by experiment to be toxic to pests, primarily soft-bodied insects like aphids, mealybugs, spider mites and whiteflies. Adult Japanese Beetles are also susceptible.

Advantages :
Insecticidal soap is one of the safest insecticides. Most non-target insects are unaffected and the soaps are not toxic to animals. Soap insecticides act fast and leave no residue. You can use them on vegetables up to the moment of harvest.
Disadvantages :
Some plants, such as peas, are readily burned by soaps, and the soaps effectiveness is greatly reduced when mixed with hard water.
How to Use :
Use against aphids, earwigs, soft brown scale, rose or pear slugs, grasshoppers, Japanese Beetles, leafhoppers, spider mites and whiteflies. Apply diluted concentrate or ready-to-use liquid when the air is still. Mix with warm, soft water and be sure to cover both sides of the leaves. Reapply after rain. Can burn the leaves of certain plants during hot weather. Apply to vegetables, fruits, shrubs, trees, or houseplants.


Neem is an extract derived from the crushed seeds of the tropical neem tree ( Azadirachta indica )

Though intensely studied for many years now, it is still a new botanical insecticide. The primary active ingredient is the compound azadirachtin, although the oils and other ingredients also have some insecticidal effect.

Neem works both as an insecticide and as an agent that prevents insects from feeding. It kills insects in the juvenile stage by thwarting their development and is most effective against aphids, thrips, mites, scale and whiteflies.

Advantages :
Neem has no measurable toxicity to mammals and is harmless to most beneficial insects. (In some countries, neem extract is considered healthful to people and is added to various foods and personal products) Recently, the Environment Protection Agency stipulated that neem was exempt form food crop tolerances because it is considered non-toxic.
Disadvantages :
There is no quick "knock-down" with neem, but a week or so after application, you should notice a steady decline in the number of pests. It is not effective against adult insects (although it may interfere with egg production) and has little impact on beneficial insects. Once beetle numbers build up in the plant, the neem no longer discourages them.
How to Use :
Neem sprays degrade very quickly in water. Mix only the amount you need and apply all of it immediately. Reapply after rainfall. On the plant, neem retains its activity against juvenile insect pests for about one week.

Use neem to kill juvenile aphids, Colorado potato beetles and thrips and to repel whiteflies, Japanese beetles, and adult Colorado potato beetles. Neem has also been found effective against spiders, cockroaches and grain weevils. It is useful as a natural remedy for head lice, scabies and mosquito and biting-fly repellant. Apply liquid spray in the morning or evening when humidity is highest. Repeat weekly, the spray lasts about one week on plants. As a toxin, apply when pests are young. As an antifeedant, neem is effective against beetles, apply before the pests appear.

As a fungicide , neem is mainly used as a preventative and when diseases are just starting to show. It coats the leaf surface which in turn prevents the germination of the fungal spores. It is effective against rots, mildews, rusts, scab, leafspot, blackspot and blights.

DO NOT USE NEEM on impatiens flowers, fuscia flowers, hibiscus flowers, rose flowers, carnations and ornamental olive trees.

Sevin (carbaryl)

One of the most widely used insecticides in home vegetable gardens, Sevin is controversial because it kills most kinds of insects. Sevin is a sledgehammer of a remedy. Use it sparingly, if at all.

Advantages :
Aside from its effectiveness, Sevin's virtue is low toxicity to mammals and birds. It is less toxic than the botanical insecticide rotenone, and is less toxic to birds than to mammals.
Disadvantages :
Sevin requires two weeks or more to degrade, so it poses a significant hazard to a wide range of beneficial insects.

Sevin is particularly deadly to honeybees and wasps, several of which are parasites of other garden pests. Because it kills beneficial insects so effectively, Sevin often causes outbreaks of so-called secondary pests, such as spider mites. Sevin is an effective insecticide against bag worm, birch leaf miner, black vine weevil, Taxus weevil, blister beetle, box elder bug, boxwood leafminer, cankerworms, elm leaf aphids, elm leaf beetles, flea beetles, Japanese beetles, June beetles, lace bugs, leaf hoppers, leafrollers, mealy bug, pine sawflies, psyllids, rose aphids, rose chafer, rose slug, scale, tent caterpillars, thrips (exposed), willow leaf beetle, ants, chinch bug, climbing cut worms, earwigs, fall army worm, fleas, millipedes, mosquitos, sod and earth worms as well as most fruit and vegetable crop insects.


Malathion is a popular and versatile broad-spectrum insecticide. It has a low toxicity and a short residual life. It can be applied on flowers, vegetables, fruit trees, shrubs and trees. It has also been proven effective as an economical mosquito control. It controls aphids, bag worm, beetles, bud moth, cabbage worm, caterpillars, codling moth, currant fruit worm, fruit moth, lace bug, leafhopper, leaf miner, leafroller, mealy bug, mites, pine shoot moth, potato beetle, tent caterpillar and whitefly.


The effective ingredient in Ambush is Permethrin which is a fast-acting insecticide for many insects. It is ideal for use in aphids, Spruce budworm, gypsy moth, tent caterpillar, potato beetle, corn borer, and many more. It can be sprayed on ornamentals, coniferous trees and shrubs, fruit

trees and vegetables. It is very toxic to fish and bees. Avoid inhaling or contact with eyes, skin or clothing.


Use Trounce on Apply to fruit trees, ornamentals, flowers, shrubs and vegetables. Do not apply Trounce to blossoms or when temperature exceeds 28C. Trounce is toxic to fish, so do not apply where runoff (into a fish environment) is likely to occur. It is a highly effective and concentrated natural insecticide, which makes it very popular. It provides a broad-spectrum control of insect pests, as listed above. Trounce does not leave a harmful residue on the plant foliage and does not emit a foul odor.

End All

End All is a formula of canola oil and pyrethrin and is effective on all life stages of aphids, spider mites, whitefly, spittle bugs, thrips, flea beetle, caterpillars, mealy bug, scale insects and sugar ants. For use on flowering plants, houseplants, woody ornamentals, bushes, trees, herbs, fruit trees and vegetables. End All can be used up to the day of harvest. It can be harmful to beneficial insects, so use care when applying and use only as a last alternative.


Rotenone is a natural, botanical insecticide that is non-toxic to bees. It breaks down rapidly and may be used up to the day before harvest on edible crops. It controls a broad range of insects on vegetables, fruits and flowers. Insects can not become resistant to Rotenone.



Defender is a liquid, sulphur based fungicide which controls the most common surface-infecting fungal problems such as powdery mildew, black spot and rust. Defender actually defend the plants by covering them with a protective coating. This product is ideal for roses as it does not have the strong smell often associated with sulphur-based products. It is ideal for use on roses, fruit trees, vegetables and ornamentals.


Funginex is an effective fungicide against powdery mildew, scab, rust and other diseases on fruits, vegetables, cereals, and ornamentals. It poses little or no hazard to fish or honey bees. Its half-life in soil is approximately 3 weeks. Do not apply on fruits later than 60 days before harvest.

Fruit Plus

Fruit plus is a formula specially developed for home orchards. It combines an insecticide with a fungicide for control of common fruit pests with a one-product application.

Garden Sulphur

Garden Sulphur is a dust that is a control treatment for powdery mildew, rust, blackspot, scab and mites. This may be used up to one day before harvest, except for wine grapes. The dust can be applied directly onto the plants or bulbs or may be mixed with water for spray applications.

Bordo Copper Spray

Bordo Copper spray is very versatile and can be used on fruit trees, ornamentals, vegetables and flowers to control leaf spot, blights, anthracnose, downy and powdery mildew and black spot. It readily mixes in water for spray applications.

Lime Sulphur

Lime Sulphur contains a calcium sulphur compound which controls fungi and also some insects and mites, and has no residual effects. It can be used as a dormant spray or growing season spray for fungal diseases, and also for scales, spider mites, rust mites, aphids, mealy bugs and peach borers. It is moderately toxic to mammals, bees, birds, and beneficial mites.


Neem, as described above, is also an effective fungicide against black spot, mildews, rust and scab.


Here is a table of treatment options depending on the pest and insect problem you are having:

Treatment Options
Problem Alternative Chemical Control
Ants Penny Royal Malathion, Ambush, Ant Killer Dust and Grub Out
Aphids Safers End All, Garlic, Petunia, White Geranium Ambush, Trounce, End All, Insecticidal Soap
Beetles Diatomaceous Earth Ambush, Malathion
Canker Worms   BTK, Trounce, End All
Caterpillars   BTK, Trounce, End All, Malathion
Cutworms French Marigolds, Nematodes, Dahlias BTK mixed with molasses, water and bran. Apply to soil
Earwigs Diatomaceous Earth Earwig Destroyer, Carbaryl Pellets (Sevin)
Gall-Forming Insects   End All
Grubs Nematodes Grub Out, Carbaryl (Sevin)
Gypsy Moth Caterpillar   BTK, End All, Trounce
Leaf Hopper   Trounce
Mealy Bugs Safers Malathion, Ambush, Trounce, End All
Mites Safers Ambush, Trounce, End All
Rose Chafer   Trounce
Scale Horticultural Summer Oil Malathion
Snails, Slugs, Sowbugs Green Chamomile, home traps, beer traps, dry dog food, eggshells Slug Pellets, Carbaryl (Sevin)
Tent Caterpillar   BTK, End All, Trounce
Thrips Garlic, German Chamomile, End All, Malathion, Ambush
Tomato Hornworm   BTK, Trounce
Viburnum Leaf Beetles   Trounce
Wasps Best Predator bug - plant members of carrot family especially Queen Anne's Lace Wasp/Hornet Spray, Wasp Traps
Web Worms   BTK, End All, Trounce
Whitefly German Chamomile, French Marigold Ambush, Trounce, End All, Whitefly Stock Traps
note: Many Chemicals are soon going off the Market


Beneficial Insects

Beneficial insects help control populations of insects that damage and destroy plants and crops. The #1 beneficial insect is the wasp family as it kills 80% of all caterpillars alone. The great majority of wasps are the size of an aphid and are in need of nectar-producing plants for food. Members of the carrot family, especially Queen Anne's Lace a prized for their ability to attract wasps. Only two members of the wasp family bite, and they are both females. First is the Potter Wasp, highly valued for paralyzing their prey (mostly caterpillars) and putting them into a solitary cell with an egg, so that when the egg hatches, the live food supply is already there. The second biting wasp is the yellow jacket, also prized due to its main source of food being the tent caterpillar and corn borers. Keep in mind that for every action, there is an equal and opposite reaction! When you kill a bug you are affecting the ecosystem that is at work in your garden. You will not attract predator bugs unless you have food (the bad bugs) for them. A well balanced garden has bad bugs, but not an infestation.

All insects play an important role in the cycle of life. It is in your best interest to allow these creatures to do their job. You can help them by making your garden as attractive to them as possible, with a variety of plants. If you use chemicals, you are interfering with, and ultimately destroying, their work .

The Scavengers :
Earwigs, carrion beetles and ants are the most important scavengers. They remove dead carcasses from your garden
The Predators :
Wasps, praying mantis, ground beetles, lady bugs, lacewings, various flies, spiders and birds are the natural answer to controlling insect populations and maintaining garden harmony.

The Beneficial Insects

  • Syrphid flies (eat aphids, leaf hopper, mealy bug)
  • Pirate bugs (eat aphids, thrips, scale and mites)
  • Lacewings (eat aphids, scale, whiteflies and mites)
  • Chalcid wasps (parasites of aphids, scale and mealy bug)
  • Spiders (eat whatever is caught in their web)
  • Tachinid flies (parasites of grasshopper, sawflies and caterpillars)
  • Trichogramma wasps (parasites of moth/butterfly eggs)
  • Bees (invaluable as pollenators)
  • Lady bugs (eat aphids)
  • Praying mantis (eat any flying insect they catch)
  • Dragonflies (eat small flying insects and mosquitoes)
  • Soldier beetles (eat cutworms, gypsy moth larvae and snails)
  • Ground beetles (eat caterpillars)
  • Braconid wasps (eat cabbage butterfly, codling moth, bark beetles)
  • Potter wasps (eat caterpillars and beetle grubs)
  • Crickets (eats aphids and other soft bodied insects)
  • Damsel bugs (prey on aphids, caterpillars and leafhoppers)
  • Eulophid wasps (eat nearly all insects, especially leaf miners and gall formers)
  • Assassin bugs (preys on ants, spiders, flies, Japanese beetles, leafhoppers and mosquitoes)
  • Blister beetles (the larvae eat grasshopper eggs)
  • Dance flies (eat black fly larvae and mites, mosquitoes, leaf miners, flies and scale)
  • Fairy flies (lays their eggs in the leaf hopper, thereby stopping further development of eggs)
  • Ichneumon wasps (lays their eggs in the sawfly or gypsy moth, up to 3000 eggs in one host)
  • Plant bugs (eats aphids, mealy bugs, slugs and scale)
  • Platygastrid wasps (controls mealy bug and midges)
  • Spider hunting wasps (the venom paralyzes the spiders, then they lay an egg on it and bury it in the ground)
  • Tiger Beetle (fastest and fiercest predator, eats ants.)
  • Nematodes(effective against caterpillars, good controller of fleas, iris borers, grubs, cabbage root maggots and strawberry root weevils)




Here is a table of common garden diseases, what they look like and how to control them.

Common Garden Diseases
Problem Damage Control / Remedy
Anthracnose Blight Long scars on leaves and fruit. Weakens fruit crops Dormant Oil Spray, Liquid Sulphur Bordo Spray, Safers Defender
Black Spot Mostly on roses and flowers. Appears on leaves, weakens crop Funginex, Floritect Combination Spray, Safers Defender
Blossom End Rot Dark blotches on tomatoes, inedible fruit Calcium based Fertilizer. Regular watering and bonemeal
Fireblight Long, Irregular discoloured scar on the trunk and stem of woody plants, black and crisp foliage No known control. Proper cultural care is best cure
Leaf Curl (Peach) Blistering effect on leaf, weakens fruit crop Dormant Sulphur/Oil Spray, Bordo, Combination Fruit Tree Spray
Leaf Spot Blistered or spotted top/bottom of leaves and flowers Sulphur, Bordo Funginex, Safers Defender
Mould (Leaf) Soft spots on leaf or stem, weakens fruit and flower crop reduce watering, Floritect Combination Spray, Safers Defender
Rot Soft Blotches on stem, root and fruit. Inedible fruit Sulphur, Dormant Oil Spray
Rust Redish/Orange 'Film' on stems and fruit. Carrier of spores Bordo, Copper Sulphate, Safers Defender, Sulphur Dust
Scale (Leaf) Blotches on fruit and leaf crop, unuseable fruit Funginex, Liquid Fruit Tree Spray
Scale Residue of the scale insect, weakens stem Dormant Oil Spray



Recipes for Alternative Sprays

These home remedies are likely to be met with varying degrees of success. Common sense is required when mixing and spraying as they contain ingredients that may harm people. Onion, garlic and tabasco juice will sting your eyes, nose and tongue. Use masks to avoid this.

Organic Pest Spray
1 pint water
½ tsp. Tabasco
1 tsp. Garlic powder (not salt)
1/4 tsp cayenne pepper
a squirt of liquid detergent
Shake well

Garlic Spray
3 oz chopped garlic, soaked in 2tsp mineral water for 24hrs
½ oz soap mixed in
1 pint of water until dissolved
Add to garlic, stir well
strain and store in glass container
to use: mix 1part to 20 parts water

Insect repellant Spray
Garlic and red pepper for sucking insects
3 cloves or 1 tbsp. Garlic powder
1 large onion
1 tbsp ground cayenne or 2 hot peppers
½ oz. Soft soap or 1 tbsp liquid soap
1 qt water
Combine and stir or blend. Let sit one hour. Strain, and store cold. Label Jar, Spray undiluted
Bordeaux Mixture Fungicide Spray
mix 50 gm of copper sulphate with 5 litres of water
Mix 50gm of hydrated lime with 1 litre of water
Add lime mixture to copper sulphate mixture and stir well
make sure there are no lumps that will clog the sprayer
Keep well mixed while using
This is an all purpose fungicide for fruit trees, small fruit and ornamentals
Rubbing Alcohol Spray
1-2 cups of alcohol with 1 litre of water.
Effective against mealybug, white fly, red spider mite, aphids and scale
Rubbing alcohol also increases the efficiency of insecticidal soap and horticultural oil. Add ½ to 1 cup of rubbing alcohol to the insecticidal soap or horticultural oil.

Killer Cooking Oil
1 tbsp of liquid dish detergent
1 cup of vegetable cooking oil
Mix together
To make a spray, mix 2 tsp of the detergent/oil mix with one cup of water.
Apply every 7 days.
Effective on aphids, white flies and spider mites.

Common Insect Pests


  • Several different varieties ranging from 3-6mm long
  • form colonies which burrow in the garden
  • no severe plant damage
  • scavengers of dead insects and natures second best pollenator



  • ½ to 2mm long
  • usually form clusters
  • can transfer viruses
  • Ladybugs, Lacewings and hoverflies will be good predators


    Chinch Bug

  • 3 to 4mm long
  • sucks juice from crown and stems of grasses
  • causes localized dead patches
  • no grass variety seems to be immune
  • forms colonies


    Mealy Bug

  • White, wooly lice
  • usually forms colonies, especially on tropicals and cactus
  • several repeat applications may be required
  • leaves mucous-like residue



  • size of a pin head
  • makes fine webbing
  • serious on indoor plants
  • sap suckers



  • hard shell casing
  • ½ - 2 mm in size
  • attaches to stem and sucks sap to feed
  • best to treat young larvae


    Snails and Slugs

  • 3-5cm long
  • slug pellets is the best control (along with other home remedies, like beer traps, eggshells, dry dog food trap, horticultural sand etc...)
  • smooth skin of tomatoes and plants will attract these pests
  • large predator of Hosta, leaves large holes in leaf



  • 1-2mm long
  • extracts sap from internal flower parts
  • leaves a sticky substance on the flower bud
  • weakens flower head



  • settles on leaf underside
  • about 2mm long
  • leaves a greasy deposit on leaves which attracts ants
  • use whitefly traps to attract and trap them


    White Grubs

  • larvae of the June Beetle
  • 2-4cm long
  • lives in the soil and feeds on grass roots
  • causes damaging bare patches in lawns
  • controlled by beneficial nematodes
  • a good lawn has 4 grubs per square foot


As you can see, there are many choices to be made on how to control and maintain pests and diseases in your garden, either by chemical remedies or natural biological alternatives. The choice is yours, but consider all reactions to the environment when making your decisions.

Read Pesticide Lables and Wear Protection !
ExperTrees wants to remind you that any insecticide or fungicide can be dangerous to apply, to humans, animals, and the plants themselves. Always protect yourself by wearing protective eye wear, gloves and dust masks. Always keep products away from the skin. Read and follow the instruction on the labels regarding storage, dilution, safe use and if necessary, first aid.



Pest and Disease management is a continually changing industry. Over the past few years, many popular chemical applications have been banned by the Canadian Government. Conversely, new natural and biological products are coming on the market, which are changing the way we look at managing insect pests and diseases in our gardens. Chemicals that were used only a few years ago are no longer available. You may still have some of these product in your garage or shed. It is not advisable to use these discontinued products, as they were taken off the market for a reason, they should be properly disposed of. Instead, look at the alternative products on the market now, that are proven more safe and environmentally responsible.