The African mallow shrub (Hibiscus acetosella) is a gorgeous flowering plant that can add vibrant colors and tropical flair to any garden. However, like many ornamentals, this beautiful shrub is prone to infestations of scale insects. These small sap-sucking pests can quickly get out of control, weakening and even killing the plant if left unchecked.
In this comprehensive guide, we will cover everything you need to know to identify, control, and eliminate troublesome scales on your African mallow shrubs.
What Are Scales?
Scales are tiny insects that attach themselves to stems, leaves, and branches of host plants like the African mallow shrub. There are two main types of scale:
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Armored scale – These scales secrete a hard, waxy shell that protects their bodies. They do not move once settled.
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Soft scale – These scales produce a cottony or waxy secretion that covers their bodies. They can sometimes move short distances.
Both types of scale feed by inserting needle-like mouthparts into the plant and sucking out the sap. An infestation can cause yellowing foliage, stunted growth dieback of branches and honeydew secretions that lead to sooty mold.
How to Identify Scale on African Mallow
Carefully inspect the stems, undersides of leaves, and junctions where branches meet the main stem. Look for:
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Small bumps or lumps on the surface that resemble shells or armor. These are the scale insects themselves.
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A sticky residue or black sooty mold, which is caused by the honeydew secretions of feeding scale.
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Distorted growth or yellowing leaves indicating sap loss.
Check closely as scales can sometimes blend in with the normal markings, texture, and colors of the plant. Use a magnifying glass to get a closer look.
Effective Ways to Get Rid of Scale on African Mallow
If you detect scale, taking prompt action is crucial before they multiply and seriously harm the shrub. Here are the top methods for controlling scales:
Prune Infested Parts
Pruning away heavily infected stems, leaves, and branches can eliminate part of the scale population. Sterilize pruners before each cut to avoid spreading scale. Remove and bag up all clippings.
Use Rubbing Alcohol
Use a cotton swab dipped in 70% isopropyl alcohol to rub off visible scales. The alcohol will kill them on contact. Be sure to get into crevices and undersides of leaves.
Apply Horticultural Oils
These oil sprays smother soft scales and suffocate armored scales by clogging their breathing pores. Spray the shrub thoroughly, especially the undersides of leaves.
Use Insecticidal Soaps
Insecticidal soap sprays will penetrate the protective waxy coatings of scales and kills them. Get good spray coverage over the whole shrub.
Apply Neem Oil
Neem oil extract disrupts the hormonal system of scales, preventing them from molting and breeding. It is derived from the seeds of the neem tree.
Release Beneficial Insects
Natural predators like ladybugs, lacewings, and parasitic wasps will feed on scale insects. These are an organic and eco-friendly solution.
Systemic Insecticides
Systemic insecticides applied to the roots or soil are taken up by the plant and make its tissues and sap toxic to feeding scale insects. Use as a last resort if other methods fail.
How to Prevent Scale on African Mallow
Here are some tips to help prevent scale infestations in the first place:
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Inspect new plants thoroughly before bringing home. Look for signs of scale.
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Quarantine new plants for a few weeks and monitor closely for pests before introducing to other plants.
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Avoid excessive nitrogen fertilization which produces succulent, tender growth that attracts scale.
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Prune African mallow shrubs in late winter to remove overwintering scale insects.
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Use row covers or insect barriers to exclude scales. Be sure to monitor weekly.
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Encourage natural predators like birds and beneficial insects by avoiding broad-spectrum insecticides.
When to Call a Professional
For severe infestations that cover large areas of the shrub, or if scales persist after multiple treatments, contacting a licensed pest control professional may be warranted. They have access to stronger insecticides and techniques to fully eliminate difficult scale problems.
Left unchecked, scale insects can quickly proliferate and devastate African mallow shrubs. By learning to recognize these sneaky pests early and taking prompt control action, you can keep your specimen looking its best and avoid major infestations. Combining good cultural practices with targeted treatments will help ensure your African mallow shrub stays vigorous and covered in beautiful blooms.
Scale: The Sticky Bandits
Waxy bumps on stems and leaves are a dead giveaway for scale insects. These freeloaders can be tough to spot, blending in with your plants natural textures.
- Catch them in the act by inspecting for unusual bumps.
- Combat them with insecticidal soap or horticultural oil.
Proactive Pest Control: Prevention is Better Than Cure
are your Common Mallows lifeline. Like a security guard on a night shift, be vigilant. Inspect leaves, stems, and soil for any signs of uninvited guests. Early detection can save you from a full-scale invasion.
The COMPLETE Guide to Getting Rid of Scale Insects
FAQ
How do you get rid of scale on shrubs?
Does vinegar get rid of scale on plants?
What insecticide kills scale?
How do you get scale off a plant?
However, unlike natural plant bumps, scale can be easily scraped off plant leaves with your fingernails. In general, scale insects target plant leaves and stems, but they often congregate on the undersides of plant leaves and around plant leaf veins.
How do you remove scale insects from plants?
Diligently removing the adult insects and spraying the larvae are sure to restore your plant to health. If you’re concerned about potential scale, you can preemptively treat your plants with diluted neem oil every few weeks. What are scale insects, and how can you get them off your plants?
What should I do if I see scale on my plants?
Scale insects reproduce rapidly and they spread quickly during their crawler phase, so it’s important to act fast if you spot scale on your plants. If you see scale on your houseplants, isolate the infected plants immediately and prune away any leaves that are badly infested with scale.
How do you treat a scale infestation on a houseplant?
When examining and treating your plant, try to do so in a well-lit room so you can better see the extent of the scale infestation. Keep your tools next to you as you go and make sure to wash your hands after removing scale from your houseplants. Scale can leave and come back, so make sure to also clean the area where you keep your plant.