Pests are a common occurence in the garden. Knowing which ones you are dealing with and how they can be controlled are common questions asked at Art's Nursery.
Aphids
Aphids are tiny 6-legged soft bodied insects that come in a variety of colours including brown, black, gray and green. They are typically found on plant stems and on the undersides of leaves. They suck sap from the plants and when digested leaves a sticky mess underneath the plant. This in turn attracts other problems like sooty mold or ants. The abundance of food allows aphids to spread rapidly to form large colonies. As the plant is weakened, damaged leaves will shrivel and curl. Aphids can be especially prevelant in dry, warm areas like greenhouses.
Controlling Aphids
There are several ways to control aphids. First, as they are soft bodied, remove them by hand or use a sharp spray of water to blast them off the plant. Aphids are not good climbers so any that you spray off will probably not return. You can also use sticky-paper bug traps. A third option is to use insectidal soap sprays that you can purchase from Art's Nursery or make yourself. Ladybugs are also a good option. Release ladybugs on the plant. Over time they will start to reduce the aphid population. Lacewings, praying mantis and a few types of wasps also find aphids very tasty. Finally, if your jurisdiction still permits the use of chemical pesticides, you may be able to find an option to control aphids.
Cutworms & Caterpillars
Caterpillars and are multi-legged crawling bugs about 1-2 inches long that are typically found on stems and under leaves. They much on foliage leaving large and irregular holes.
Cutworms are typically gray or cream coloured with black accents and are often found under leaf debris or in the soil. When disturbed they often curl into a "C" shape. They are notorious for cutting off seedlings at soil level.
Controlling Caterpillars and Cutworms
The most environmentally friendly method of dealing with these pests is to cultivate your soil in the Fall. this kills overwintering eggs. You could also apply beneficial nematodes in the spring or fall to attack the larvae and juvenile pests. As caterpillars and cutworms are larger, they can also be removed by hand. If available, you can also spray with products that contain BT or Bacillus thuringiensis. Cutworms and caterpillars are also preyed upon by certain wasps and flying insects.
Slugs
Slugs are the nemesis of most gardeners. They common in a variety of shapes, colours and sizes but all are sticky, slimy and soft bodied. They leave slime trails as they travel and chew on leaves they find tasty.
Controlling Slugs
There are many ways to control slugs, but be forewarned, it is not a sprint, it is a marathon. Slug control is something you will have to practice regularly. As they are large, remove them from your garden by hand (or glove!). During the day, they hide underneath objects in your garden. At twillight and through the night they cruise through the garden looking for a meal. Therefore, going out with a flashlight at twillight or in the dark will maximize your harvest. Beer traps are also effective, fill a small deep container with beer and sink it into the garden. The slugs will get thirsty, fall in and drown. We recommend using cheap beer... :)
If you are feeling particularly nasty, spraying slugs iwth a 50-50 Ammonia / water solution or sprinkling them with salt can also be entertaining. As the slugs have soft underbellies, they dislike crossing anything sharp. Sprinkle your garden with coffee grounds, sharp sand or a product known as Diatomaceous Earth. A slugs slime trail reacts when it comes in contact with copper. Line edges of raised beds or containers with copper strips - they will not cross it.
There are also several slug control products on the market that poison them on contact. The number of chemical options is on the decline as governments legislate cosmetic pesticide bylaws.
The last option for slug control is to introduce them to other members of the food chain. Slugs make a nice meal for frogs, toads, snakes and ducks.
Snails
Snails are soft bodied creatures that travel around in hard, strangely attractive, shell. They are partners in crime with the slugs. They cruise around in your garden after-hours and chew away the foliage in your garden.
Controlling Snails
You can control snails in many of the same ways you control slugs.
Root Weevils
The presence of root weevils can often be confirmed if you notice squared-off notches in your leaves. The white larvae feed on plant roots, while the black, non-shiny adult weevils chew on leaves in late spring and early summer.
Controlling Root Weevils
Controlling root weevils is a multi-stage process. Use Beneficial Nematodes to the soil in fall and spring in order to kill off the larvae. To deal with adult populations, ensure that any branches of leaves that touch the ground are pruned away or moved. Use a sticky product like 'Tanglefoot' to trap adult weevils. Root Weevils often do their dirty work in the evening. Look for adults in the dark with a flashlight and pick them off. Another option is to place a white sheet underneath the plant and shake them off and destroy them. If available in your area, you can also spray your plant with neem oil.
Earwigs
Earwigs are long, black or brown coloured, 6-legged pests with pincers near their back end. They chew holes into leaves causing them to brown and shrivel.
Controlling Earwigs
Earwigs are drawn to damp, dark places. Place damp, rolled up newspapers on the ground. Dispose of these traps in the morning. Another option is to fill small cans with vegetable-oil and place at ground level. Dispose of the traps when they have caught the pests. Diatomaceous earth and insecticidal soaps are also effective controls. If you can encourage wildlife into your garden, you will find that toads, frogs and birds will also eat earwigs and control their population.
Ants
While Ants may be nuisance, they don't harm plants directly. What they are guilty of is farming aphids. They will often encourage aphids populations in order to harvest the sticky sap for their own benefit. If ants are a pest in your garden, lay out ant bait. To destroy an accessible nest, try pouring several jugs of boiling water into it. If the ants in question are large or are finding their way into your home, they may be carpenter ants. If in doubt, call a reputable pest control company.
Scale
Scale are insects that suck plant juices from under the safety of a waxy, usually brown coloured shield or scale. They are often found on houseplants or juicy tropicals.When in their protected stage they are generally immobile and can be picked off by hand or fingernail. Heavily infected sections can also be pruned off. In their juveline stage, apply horticultural oil or insecticidal soap. Ladybugs and certain types of wasps also find scale to be tasty.
Spider Mites
Spider Mites are tiny, almost invisible, sucking insects of various colours, including green yellow or red, with two dark spots. To spot them, place a piece of white paper below and shake the foliage. Notice if any small dots fall and move around on the paper. Spider Mites favour warm, dry areas and leave a telltale stippling of yellow dots on leaves and a fine webbing. They are often found on the underside of leaves and within the interior of the plant.
Controlling Spider Mites
The first line of defence is to increase humidity or moisture. Spider mites like it dry, not wet. Spray the insides of plants with water, or wipe larger leaves with a wet sponge or cloth. Mist occasionally. You can also spray with horticultural oils, insecticidal soaps or with organic pesticides that control mites. Beneficial insects like ladybugs, lacewing larvae or predatory mites can also be effective controls.
Mealy Bugs
Mealy bugs resemble small white cotton swabs attached to the leaves and stems of your plant. They damage your plant by sucking the juices and are often found where leaves join stems. They are quite common on houseplants and succulents.
Controlling Mealy Bugs
To control mealy bugs, wash them off with a wet sponge and soapy water. You can also dab them with rubbing alcohol.
Furry Critters
While we don't consider our dog to be a critter, sometimes the neighboring cats, dogs, deer or even squirels and chipmunks can be a nuisance. Cats tend to be diggers. Use netting and chicken wire to reduce the areas available to them. They dislike getting wet, so a squirt gun can be effective. To make your garden less entertaining for dogs, plant thickly and make the area unfriendly. Sharp or pointy plants like barberry are a good choice. Various commercial products are also available like 'Critter-Ridder'. To deter squirrels and chipmunks, plant your bulbs underneath chickenwire or dip them in Bobbex. Deer are particularly challenging foe. Use fences, as well as repellent sprays like Plantskydd or Bobbex.
For additional information about these common garden pests, please feel free to call Art's Nursery during business hours at 604.882.1201 or drop by and visit us in person