How to Get Rid of Aphids Naturally: 10 Ways
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Aphids are not only a nuisance but they damage and slow the growth of common plants like hydrangea, birch, and viburnum. With so many options to get rid of aphids naturally, there is no need to resort to harmful chemical pesticides.
Meet the Expert
Petar Ivanov is a gardening and plant expert at Fantastic Gardeners, a gardening and landscaping company in London, England.
Jana McDaniel is the founder of First Saturday Lime, a pesticide alternative.
What Aphids Do in the Garden
Aphids damage plants but rarely kill them. Aphids and their eggs can stunt plant growth; the plant's leaves curl and discolor; flowers and fruits grow slower and smaller; and some aphids can transmit viruses.
Aphids suck up plant sap. They excrete a sticky sap, called honeydew, back on the plant's leaves and stems.
Honeydew also encourages the growth of black sooty mold, a fungus that darkens the plant and hampers the plant's ability to receive sunlight.
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Checklist
Aphids frequently infest beans, cabbage, cucumber, melons, ash, birch, elm, hydrangea, linden, maple, oak, pine, and many other shrubs, plants, and trees.
Signs You Have Aphids
The first step in getting rid of aphids is identifying them and their effect on plants. Your plants likely have aphids if you notice:
Aphid colonies
Aphid eggs
Stickiness
Shiny film
Dark sooty mold
Curled leaves
Yellowed leaves
Stunted growth
Remove Aphids by Hand
Remove aphids by hand as an immediate though slow way to get rid of aphids from your plants.
Wear waterproof gloves. Gently rub the leaves and stems between your fingers to scuff the aphids off or to crush them.
Aphids proliferate rapidly, and each egg produces about 40 to 50 more aphids. So, you'll need to repeat the process every few days and make sure that you remove every aphid and egg.
Knock Off Aphids With Water
Spray aphids off your plants with a hose nozzle attached to a garden hose. The spray doesn't kill the aphids but it does knock them off of the plants.
Knocking off the aphids is a fast, short-term solution. It removes more aphids than rubbing them off by hand. But it does so indiscriminately, so flowers and other desirable plant parts may be removed. Also, it can damage delicate leaves.
The best hose nozzle for spraying aphids off plants will offer many spray patterns. Choose a low-pressure spray pattern to protect your plants.
Tip
Blasting plants with a garden hose isn't an option if you need to control aphids on indoor house plants. In this case, use a hand-pump spray bottle filled with clean water or remove the aphids by hand.
Spray Plants With Garlic
Apply a homemade spray for fighting aphids. Garlic has long been used to get rid of aphids. Garlic has an added benefit: sulfur. Sulfur slows the growth of bacteria and fungi.
Grate or chop four garlic cloves, add two teaspoons of mineral oil, and let it rest for a full day. Add two cups of water. Strain out the solid pieces, leaving only the garlic solution.
Dilute the garlic solution even more when you add it to the garden sprayer. Test the solution in one section of the plant before spraying the entire plant.
Tip
While a hand-pump sprayer is appropriate for small plants, the best garden sprayer for shrubs and trees will be larger, with a minimum capacity of one gallon.
Apply a Tomato Leaf Solution
As with garlic, tomato leaves contain ingredients that can work as insecticides and repel aphids. It's simple to make.
"To create a solution, soak two cups of fresh tomato leaves in water overnight, strain the liquid, and spray it on your plants," advises Petar Ivanov, gardening and plant expert at Fantastic Gardeners.
"Besides aphids, this natural insecticide kills many other chewing insects and attracts beneficial ones," Ivanov says. "But this solution isn't equitable for crops such as eggplants, peppers, and potatoes because it can spread disease on them."
Spray Plants With Neem Oil
Use neem oil as an organic insecticide to get rid of aphids, as well as mites and fungi. Some trees, such as flowering dogwood and Colorado blue spruce, respond especially well to neem oil treatments.
Neem oil is derived from neem tree seeds, its active ingredient being azadirachtin, which repels and kills pests.
"Neem oil disrupts the lifecycle of pests and can be effective against a variety of insects, including aphids," Ivanov says.
Tip
Start with a teaspoon of dish detergent in a gallon of lukewarm water. Mix well. Then, add a teaspoon of neem oil. Pour in the garden sprayer and liberally coat the plants.
Introduce Aphid Predators
"Effective natural aphid control employs an integrated approach, including introducing beneficial insect predators," says Jana McDaniel, founder of First Saturday Lime. "Ladybugs and lacewings are nature's little guardians against these sap-sucking pests."
Other aphid predators include syrphid fly larvae, soldier beetles, and minute pirate bugs.
Tip
Do not introduce ants to aphids. Ants and aphids help each other—symbiosis. Ants consume aphids' honeydew and ward off aphids' predators.
Add Repellant Plants
Get rid of aphids on plants over the long term by adding plants that repel the aphids.
"Companion planting with aromatic herbs and flowers like chives, petunias, and marigolds creates a pungent, visually deterring force field," McDaniels says. "These plants release confusing scents and phytochemicals that repel aphids, while their bright colors and dense foliage act as physical barriers."
Ivanov, too, recommends planting marigolds.
"These flowers are known to deter pests, including aphids, whiteflies, and some beetles," Ivanov says. "The best marigold varieties for insect repellent purposes are African and French marigolds. Both varieties contain natural compounds that repel insects."
Add companion plants near the host plants affected by aphids. Aphids find the companion plants more attractive than the host plants.
Tip
Other plants that repel aphids are basil, chives, catnip, onion, leeks, radishes, and allium.
Spray a Soapy Solution on the Plants
Mild dish soap is used as an emulsifier with other organic aphid pesticides like neem oil and tomato leaves. But it can be used on its own, too.
"A simple solution of mild dish soap and water can be an effective insecticidal soap and also particularly effective if you're dealing with aphids," Ivanov says.
He adds that dish soap can also deter spider mites and whiteflies. Mix equal parts of dish soap and vegetable oil, dilute it with water, and spray it on your plants.
After a few applications of this solution, Ivanov says, rinse the plants with clean water, especially if there has been no rain to wash the residue off.
Use Reflective Mulch
To get rid of aphids around garden beds, roll out silver-colored plastic. You can also install landscape fabric coated with silver paint.
Bright, silver-colored reflective mulches are proven to repel aphids on garden beds. In addition, reflective mulches send more solar energy to the plants, resulting in larger, healthier vegetables.
Reflective mulch can be as simple and cheap as aluminum foil. But foil tends to be too fragile for exterior use. It's best to look for a silver or gray reflective mulch or mesh made expressly for this purpose.
Reduce the Nitrogen
Remove aphids by reducing the nitrogen content in over-fertilized plants or switching to organic fertilizers.
All plants require nitrogen in their soil. But excessive nitrogen sends plants into overgrowth mode. The aphids notice the overgrowth, respond to it, and reproduce more rapidly.
Switch from a chemical fertilizer to an organic fertilizer. Made exclusively from minerals and from organic materials like manure, fish emulsion, and leaf mold, organic fertilizers release nitrogen at a slower rate.
For persistent aphid problems, you can even choose an organic fertilizer with a higher proportion of minerals to organic matter for a slower nitrogen release rate.
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Read the original article on The Spruce.
