The African mallow shrub (Hibiscus acetosella) also known as the cranberry hibiscus is a beautiful and hardy plant. Unfortunately, it is prone to infestations by a common garden pest – the aphid. These tiny insects can quickly damage the leaves and stems of the African mallow if left unchecked. But there are several effective and organic methods for getting rid of aphids on this plant. In this guide, we’ll cover how to identify and prevent aphid infestations on African mallow shrubs, as well as the best treatment methods.
Identifying Aphids on African Mallow
The first step is learning how to identify an aphid infestation Here are the signs
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Presence of aphids – Check the stems and undersides of leaves for clusters of small, soft-bodied insects. Aphids can range in color from green, yellow, black, red or brown.
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Sticky residue – Aphids secrete a sticky, sugary substance called honeydew. This can coat leaves and stems.
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Curled, wrinkled or yellowing leaves – Aphid feeding causes distorted growth and discoloration.
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Presence of ants – Ants feed on the honeydew and will actually protect aphids
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Sooty mold – This black fungus grows on the honeydew.
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Stunted growth – Heavy aphid feeding prevents proper growth.
Check plants frequently, especially new growth, for the earliest signs of an infestation. Take action quickly to limit damage.
Preventing Aphids on African Mallow
While aphids can’t be completely prevented, you can make your African mallow plants less appealing:
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Remove weeds – Eliminate other hosts that aphids feed on.
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Use reflective mulch – The light deters aphids from landing on plants.
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Apply horticultural oils – These oils coat and suffocate insects.
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Use row covers – Floating covers form a protective barrier.
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Introduce beneficial insects – Ladybugs, lacewings, and other predators eat aphids.
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Practice crop rotation – This prevents pest buildup over seasons.
Organic Ways to Get Rid of Aphids
If prevention fails and African mallows become infested, it’s important to act swiftly. Here are some safe, natural methods to eliminate aphids:
Insecticidal Soaps
Insecticidal soaps containing potassium salts of fatty acids disrupt the waxy coating on insect bodies, causing dehydration and death. Spray directly on aphids. Repeat applications are needed.
Neem Oil
Extracted from the neem tree, this oil coats insects, deterring feeding and interrupting reproduction. Mix with water and spray. Reapply every 1-2 weeks. Do not apply during hot sun or blooming.
Horticultural Oils
Lightweight oils like canola oil smother soft-bodied insects like aphids. Coat all leaf surfaces for best results. Apply weekly for heavy infestations.
Pyrethrins
Pyrethrins are plant-derived pesticides found in chrysanthemum flowers. They attack the nervous system of insects. Spray in the early mornings or evenings for safety.
Homemade Sprays
Mix 1 tablespoon liquid soap with 1 quart water. Add several cloves of crushed garlic or 1 teaspoon cinnamon for extra insect-repelling power. Coat leaves, rinse off after a few hours.
Forceful Water Spray
Set your hose nozzle to a strong stream of water. Directly spray aphids off leaves and stems. Focus on the undersides of leaves. Repeat daily as needed.
Biological Controls
Release beneficial predatory insects like ladybugs, lacewings, and hoverflies. They’ll naturally control aphid populations. Also attract insectivorous birds to your yard.
Companion Planting
Interplant African mallows with aromatic herbs like basil, mint, sage, garlic, and chives. Their strong scents help repel aphids.
How to Care for Aphid-Damaged African Mallows
After an aphid attack, African mallow plants need some TLC to recover. Here are a few tips:
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Remove badly damaged leaves and stems to promote new, healthy growth.
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Apply a nitrogen-rich fertilizer to stimulate regeneration after insect feeding.
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Use a damp cloth to gently wipe off any remaining honeydew residue.
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Keep plants well-watered during regrowth.
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Monitor for signs of secondary infections like sooty mold and treat if needed.
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Place diatomaceous earth or crushed eggshells on the soil to prevent re-infestation.
With diligent monitoring and the use of organic control methods, aphids can be safely eradicated from African mallow shrubs. It may take repeated efforts, but you’ll soon be rewarded with happy, thriving plants again. Don’t let these tiny pests get the best of your beautiful African mallows!
Answer:Jonathan Foster, Special Project Assistant
I’m sorry to hear about your aphid woes–I recently dealt with an outbreak on my indoor purple passion plant. As you note in your question, 1) aphids are often not a huge problem as long as their population is kept in check, and 2) once they reach a critical mass, they can be quite a nuisance. The most organic method of control, and often a quite effective one, is the spray of water. Soapy water can help kill the aphids, as it sounds like you know, but a particularly strong jet of water will dislodge/kill most of them physically, as well. So I suggest trying that if you haven’t yet.
If that hasn’t worked, though, I recommend reviewing our UMaine Cooperative Extension Pest Mgmt Fact Sheet #5039 for suggestions on chemical control. As you will read, the treatments (in rough descending order of “organicness”) are insecticidal soap, horticultural oil, neem oil, and malathion. I will note that insecticidal soap worked well for me with my purple passion, but it does require direct contact with the aphid to kill them and it washes off easily and must be reapplied.
As always with chemical interventions, please read the instructions carefully and follow them diligently to achieve maximum effectiveness and to protect yourself and the environment.
How do I manage a large outbreak of aphids?
I have a huge burning bush. The last few years I have been battling aphids. Last year I didn’t do anything and realized the problem wasn’t that bad after not spraying it with soapy water as usual. This year, however, they are incredibly bad. They seem to have taken over the entire bush, including the not so new growth. Additionally, I have them in a nearby holly (they haven’t been there before), and in perennials I have planted beneath the bush. This morning I have found some in my nearby flower bed. I am loath to use pesticide, but now will, but I’m not sure how to treat a shrub so large and what with. Looking for advice. I don’t want to kill pollinators and a lot of my flowers attract hummingbirds.
Foolproof Aphid Control and Prevention
How do you get rid of aphids on plants?
Use a strong spray of water to knock aphids off your plants. Of all the natural remedies for getting rid of aphids quickly and effectively (not to mention inexpensively), a simple, strong blast of water is one of the best and easiest ways to control these pests.
Can neem oil kill aphids?
“Neem oil disrupts the lifecycle of pests and can be effective against a variety of insects, including aphids,” Ivanov says. 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.
Which plants repel aphids?
Aphids find the companion plants more attractive than the host plants. Other plants that repel aphids are basil, chives, catnip, onion, leeks, radishes, and allium. 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.
How do you get rid of aphids with garlic?
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.