How to Control Aphids Using Beneficial Insects

Many plants, from berries to vegetables, benefit from natural enemies that consume aphids; however, when their populations multiply rapidly they can cause severe damage to plants.Plants affected by aphid infestation often become disfigured and overgrown, as aphids secrete a sticky honeydew-like substance, which attracts sooty mold growth. An outbreak usually begins with winged aphids flying about in search of hosts; such infestations quickly multiply.

Identify Beneficial Insects

Natural enemies of aphids include lady beetles, lacewings, and parasitic wasps as effective predators of this pest. Ground beetle larvae as well as some syrphid fly larvae and brightly colored hoverflies, are known to consume numerous aphids before becoming winged adults themselves. Some species of nematodes can help control aphids as well. Nematodes are soil-dwelling insects often buried deep within the roots of vegetables and flowers. While most commonly introduced through purchased packages, native plants such as clover and alfalfa can also host these beneficial insects. To attract beneficial insects, create an ecosystem that offers both food and shelter. Plant flowers with long-acting pollen sources to attract pollinator bees; select easy-grow varieties suitable for pollinator bees. Mulch or ground covers offer cool shaded spots where beneficial insects can find shelter from sun. Using floating row covers protects early-season vegetable and berry-plant seedlings from insects such as aphids. When the crop reaches several inches in height or when the weather becomes warm and dry, remove the covers as necessary.

Create a Favorable Habitat

Aphids feed on plant juices, depriving plants of essential nutrients and transmitting diseases. Furthermore, honeydew produced by these insects attracts ants which in turn can result in sooty mildew or black mold growth resulting in black mold known as sooty mildew growth. Aphid populations grow quickly as one winged female can produce up to 41 generations in one season. Wingless adults disperse to new host plants using flying ability and leave irritating leaves in their path. Green Lacewing Larvae are highly effective all-round aphid predators. Start attracting these insects early by providing annual flowers and herbs such as Alyssum, Calendula Marigolds, Cosmos Nasturtium Sunflower Zinnia Zinnias Zinnias, etc as well as perennial Herbs like Dill, Fennel Coreopsis Tansy to attract these bugs early. Unless the aphid population is controlled quickly and efficiently, their honeydew production will quickly be eradicated, leading to leaves with distortions, curling, yellowing, and stunted shoot growth. A vigorous spray of water early in the day will quickly reduce aphid numbers while washing away their honeydew deposits; applying sprays in areas where there are already clustered populations will ensure they can’t regroup back in one location again and return later.

Avoid Insecticides

Aphids may appear small, but their numbers can quickly overwhelm plants without effort. Furthermore, female aphids lay unfertilized eggs within themselves rather than on the host plant itself – another aspect that makes aphids such a formidable enemy of plants. There are, fortunately, several natural methods of dealing with heavy aphid infestations without resorting to chemical treatments. Spraying leaves, stems, and buds of infested plants with insecticidal soap (or horticultural oil) will quickly kill off pests without harming plants; or gently rub your fingertips over them until you notice the number of aphids begins decreasing. Repeat these treatments frequently until their population begins to decrease. Flowers such as marigolds, dill, fennel, or alyssum should be planted near infested vegetables or fruits to attract beneficial insects that feed on aphids and other pests. Herbs such as sage, tarragon, and parsley also help draw these predators to your crops – such as ladybugs, lacewings, damsel bugs, syrphid fly larvae, and parasitic wasps can serve as natural enemies that feed on these pests – eventually paralyzing them so much that their skins turn golden brown giving them the appearance of being mummified.

Introduce Beneficial Insects

Aphids excrete honeydew when feeding on leaves or stems, which attracts insects such as ants. Honeydew may also foster sooty mold growth, which coats leaves and stems with black, splotchy spots resembling sooty mold; sooty mold may even attach itself to cars, patio furniture, and other outdoor structures – further spreading its effects. Aphid infestations can seriously compromise plant health, leading to stunted growth, discolored leaves and flowers, and reduced seed production. Established plants typically tolerate moderate-heavy infestations of aphids without suffering further stress from other factors like drought. An assortment of predators and parasitoids are available to control aphid populations. Commercially available lady beetles (such as Hippodamia convergens) and lacewing larvae can provide effective control when used regularly, while natural enemies include syrphid fly larvae and soldier beetles. Botanical insecticides like Neem, Pyrethrins, and Rotenone offer shorter active times than synthetic options and breakdown more quickly when exposed to sunlight.

Monitor and Adjust

Aphids can cause serious problems for plants by stripping them of nutrients, spreading disease and creating sticky black galls on leaves and stems. Furthermore, they feed off roots as they migrate. One female aphid hatching in spring can produce up to 41 generations of offspring! Carefully watch and remove any aphids you find on your vegetables, flowers, or trees. Watch for signs of severe infestation, such as curled and distorted leaves as well as poor plant growth caused by these pesky insects. Generally, severe infestations do not harm overall plant health, and nonchemical controls may effectively control them. As spring begins, protect young vegetable plants with floating row covers to keep aphids away while still allowing air, light, and water in. Use it when transplanting seedlings but remove it once seedlings have reached several inches tall or as temperatures warm in summer. Consider planting herbs such as dill, fennel, cilantro, or chives that repel aphids using strong scents – these could work just as effectively – or planting trap crops–sacrificial plants which attract them away from more valuable crops.

Maintain Plant Health

Plants often tolerate small populations of aphids, which feed by sucking away plant juices from leaves and stems without suffering serious consequences. But when their numbers increase uncontrollably, aphids can quickly cause havoc for crops – but natural methods are available to control aphids. Before resorting to harsh insecticides, create your own homemade insecticidal soap which will desiccate aphid soft bodies without harming the plant. Mix a teaspoon of alcohol or mild liquid dish soap into 1 quart of water and spray or wipe onto leaves, buds, stems or roots affected by aphids as needed – repeat as necessary. Lacewings, beetles, and green flies (Syrphid flies) are other effective natural enemies of aphids; look out for predatory insects with piercing or sucking mouthparts that fly efficiently if in your garden and near other infested crops. Syrphid fly larvae feed on aphids as well as transmit viruses from one plant to the next on squash, melons, beans peas potatoes and lettuce plants in particular. Other ichneumonid parasitic wasps lay their eggs within aphids, which then swell up and turn golden brown (a condition known as mummification), drawing the attention of bees and other pollinators. These golden brown mummified bodies attract pollinators such as bees.

Encourage Biodiversity

Lady beetle adults and larvae, lacewing larvae, soldier beetles and syrphid fly larvae can all serve as effective natural defenses against aphids, with ladybeetles being particularly effective when applied before populations reach critical mass. Commercial insect predators like these should also be applied before an infestation has become problematic. These insect predators should ideally be applied early each spring before populations of aphids reach critical mass levels. Aphids produce honeydew as they sucking sap from trees, which ants feed upon. Ants love this treat and gather up honeydew using special tongue parts known as stylets, later taking it back to their colonies where they feed it back out as food for other ants. Ants also act to shield aphids from predators, offering protection from feeding damage as well as spreading diseases and viruses. Some species produce cupped leaves that are unsightly to look at; many plants become stunted or even die due to these attacks; these attacks become especially severe during drought conditions when protective chemicals produced by plants diminish, making plants susceptible to attack by aphids; infestations symptoms include curled and twisted leaves, wilted shoots or unopened flower buds.

Practice Crop Rotation

Infestations is often spread by winged aphids flying to nearby plants or crops and feeding, laying eggs, transmitting viruses that stunt or kill host plants, draining off valuable nutrients from them, resulting in cupped or distorted leaves as a result of feeding activity; blackflies (Aphis fabae) are notorious for this – some even cause galls on leaves and stems which is potentially detrimental. Aphids have soft bodies that make them vulnerable to many natural controls, such as sprays that disrupt their membranes and suffocate them. Alcohol or soap sprays should be applied early in the season on only infested areas – residue-free sprays tend to be less harmful to existing beneficial insects than chemical-based solutions. Crop rotation can help your garden or farm to enhance soil health, increase the availability of nutrients, and ward off diseases and pest pressures. Planting flowers that bloom at different times, such as marigolds, buckwheat, tansy leaves, and sunflower seeds, can attract predators and parasites that help control aphids effectively.