Order: Hemiptera (TrueBugs)Family: Psyllidae, TriozidaeCommon Names: Plant Lice, Jumping Plant Lice, Lerps, Lerp Psyllid, Gall Psyllid, Lilly Pilly Psyllid
Psyllids are tiny sap-sucking insects that feed on the nutrient rich liquids inside leaves and transport tissues (xylem & phloem). Most species of psyllid will only feed on one specific host plant, however some species are known to broaden their preferences to plant varieties within the same family.
The African mallow shrub (Malvaviscus arboreus) is a beautiful tropical plant prized for its lush green foliage and showy blooms in shades of red pink and white. However, these ornamentals can fall victim to infestations of tiny sap-sucking insects called lerps. Left uncontrolled, lerps can seriously damage African mallow shrubs by stunting growth and causing leaves to yellow, wilt, and drop.
If you’ve discovered lerps lurking on your African mallows, don’t panic. By learning to recognize these pests and taking prompt control measures, you can successfully get rid of lerps and restore the health and vitality of your plants.
What are Lerps?
Lerps are small, flattened insects in the Psyllidae family that feed on plant sap. Most sport a protective covering of waxy secretions that give them a bumpy, armor-like appearance. These tiny pests pierce plant tissues and suck out sap, weakening the plant and providing entry points for disease.
Lerps love succulent new growth and often cluster on the undersides of leaves or on tender stems and shoots. Left uncontrolled lerps can multiply rapidly leading to stunted, sickly plants. Their sugary honeydew secretions also promote mold growth.
Signs of Lerps on African Mallow
Detecting lerps early is key to effective control. Watch for these telltale signs:
- White or brown bumps on leaves, usually clustered on the undersides
- Sticky honeydew coating on foliage
- Distorted, curled, or thickened leaves
- Poor growth and leaf drop
- Fine webbing on stems and shoots
Carefully check the undersides of leaves and new growth where lerps tend to hide, Early intervention can help nip infestations in the bud
Safely Eliminating Lerps from African Mallows
When lerps are detected on an African mallow, take prompt action to get rid of these pests and prevent further damage:
Remove Heavily Infested Growth
Prune off severely infested leaves, stems, and shoots using sterilized pruners. Dispose of the trimmings in sealed bags to prevent spread. This immediately eliminates large lerp populations.
Hose Off Plants
Use a strong stream from the garden hose to physically dislodge lerps from leaves and stems. Focus on the undersides of leaves and new growth. Repeat regularly to control heaviest infestations.
Apply Neem Oil
Neem oil is a natural insecticide that disrupts lerps’ growth and reproduction. Dilute with water per label instructions and thoroughly coat all leaf surfaces, especially the undersides. Reapply every 7-10 days until lerps are gone.
Release Beneficial Insects
Natural predators like ladybugs, lacewings, and parasitic wasps feed on lerps. Introduce these beneficials to your garden and grow companion plants to attract and retain them.
Use Insecticidal Soap
Insecticidal soap sprays are effective and safe for African mallows when used as directed. Spray plants, targeting the undersides of leaves, to kill lerps on contact while sparing beneficial insects.
Apply Horticultural Oil
Horticultural oils smother lerps’ eggs and nymphs on contact. Coat leaves, stems, and shoots thoroughly for best results. Reapply every 7-14 days until infestation clears.
With persistence and vigilance, you can eradicate destructive lerps from your African mallows using these safe, effective control methods. Always follow label directions when using any pest control products.
Preventing Lerps from Returning
Prevention is the best way to avoid lerp infestations recurring on vulnerable African mallow shrubs. Here are some tips:
- Inspect plants frequently, especially new growth, for signs of lerps
- Remove and destroy any infested parts immediately
- Trim plants to improve air circulation and make inspection easier
- Water at soil level and avoid wetting foliage excessively
- Apply horticultural oil or neem oil preventatively every 2-3 weeks
- Avoid excess fertilization, which stimulates tender new growth lerps prefer
- Introduce and conserve beneficial insects like ladybugs and lacewings
- Monitor for and control common lerp predators like ants
With diligent monitoring and care, you can help keep lerps at bay and your African mallows healthy and thriving despite this pest challenge. Don’t hesitate to take action at the first sign of lerps before they multiply and cause significant damage. Combining prevention with prompt control measures offers the best protection against lerps on ornamental African mallow shrubs.
Other Pests That Attack African Mallow
While lerps are one of the most troublesome pests for African mallow shrubs, a few other bugs can also infest these plants. Be on the lookout for these as well:
Spider Mites
Tiny spider mites suck sap and cause stippling damage. Knock them off with jets of water and apply insecticidal soap spray.
Aphids
Green, yellow, or black aphids cluster on stems and undersides of leaves. Use horticultural oil, neem oil, or insecticidal soap to control.
Whiteflies
These flying pests cause yellow stippling on leaves. Use sticky traps and horticultural oil to reduce populations. Prune out heavily infested growth.
Mealybugs
Cottony mealybugs on stems and leaves excrete sticky honeydew. Use alcohol on a cotton swab to kill them or apply neem oil spray.
Be vigilant for signs like honeydew, stippling damage, or visible pests. Identify the problem accurately so you can take appropriate control measures. Keeping African mallow shrubs healthy overall helps deter infestations.
Provide Good Care for Your African Mallows
The best offense against pests like lerps is a good defense. Keep your African mallow shrubs healthy and vigorous by providing good care:
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Site in full sun to partial shade where they’ll get 4-6 hours of direct light daily
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Plant in well-draining soil enriched with compost
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Water deeply whenever the top few inches of soil become dry
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Fertilize monthly in spring and summer with a balanced liquid fertilizer
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Prune periodically to remove dead wood, shape, and improve air circulation
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Monitor for pests and diseases and take prompt action at first signs
Healthy, thriving African mallow shrubs are more resilient against destructive pests like lerps. Proper care makes them less inviting to infestations. Be attentive to their needs for sun, soil, moisture and pruning for maximum health.
Enjoy Lerp-Free African Mallows
Don’t let annoying lerps stop you from enjoying the graceful beauty of African mallow shrubs. By learning how to recognize, control, and prevent lerp infestations using safe, effective methods you can continue to cultivate these enchanting plants and have them enhance your garden for years to come.
With diligence and dedication, you can outsmart destructive lerps and keep your African mallow shrubs looking their best. The effort to eliminate and exclude these sap-sucking pests is well worth it to be rewarded with an abundance of glossy green leaves and colorful, pendant blooms adorning your garden spaces.
What do Psyllids look like?
Psyllids have 3 life-cycle stages: egg, nymph and adult. Most species will go through 3 to 5 generations per year.
Adults look like a tiny, winged insect approximately 2-3mm in length, the wings pointing back over the abdomen in a V shape.
Nymphs are usually a miniature version of the adult form but without wings, more scaly and can look flattish. Some species hide under what is a called a ‘Lerp’, which is a little white, sugary covering that shields the nymph whilst it feeds and molts. Others cause pits or galls in the leaves.
Eggs are found singly or in clusters, sometimes found upon the leaf and its edges, other species insert the eggs into the leaf tissue.
What are the signs that you have Psyllids
We have 100s of species of psyllids in Australia. The most common species are the Lilly Pilly Psyllid, Lerp forming Psyllid, Gall forming Psyllid and Free Living Psyllid. These are all mostly found on our native plants and are most noticeable during the nymph stages.
These psyllids are often visible on the new growth of the plant. After they hatch, the nymph crawls into position on a young leaf to begin feeding and molting. After the first molt a pock mark or small pit appears on the leaf. As it grows and continues to molt, this pit becomes bigger, looking like a pimple on the leaf of the plant. The adult emerges after the final molt and the whole cycle begins again! Waterhousia floribunda is a particularly juicy variety to the Lilly Pilly Psyllid and often gets attacked.
Damage
Cosmetic damage to the leaves, causing the leaves to curl and pimple. Severe infestation can cause some leaf drop and stunt growth but it is rare that it will kill the plant.
Often seen on natives such as Eucalyptus, the nymphs will burrow into the leaf, causing a gall to form around it as protection. Once the nymph has reached maturity, it breaks out of the gall as an adult.
Damage
Only cosmetic, overall never getting so bad as to kill the tree.
These psyllids excrete a white, sugary substance to cover themselves as protection whilst they feed on the leaf of the plant. This is called a lerp. The lerp gets bigger as the nymph molts, finally emerging as an adult. Lerps are eaten by many animals such as birds, possums, flying foxes and gliders. They can even be eaten by humans as a sweet treat!
Damage
Light infestations cause a mottled appearance on the leaves, whereas a severe infestation can cause the tree to defoliate, affecting its growth and appearance. In some cases it can cause the tree to die.
Free-living psyllids are just that, free living! They feed on the new growth of the plant and create no protective cover like the previous psyllid types. Both the adult and nymphs are seen on the plant at the same time. They tend to target a lot of natives such as grevillea, wattles and eucalypts as well as ornamental plants such as Smoke Bush.
Damage
Can produce Sooty Mold and other waxy secretions, often deforming new growth with bad infestations.
How to Get Rid of Mealybugs – Part 1 of Logee’s “Pest Prevention” Series
FAQ
How to get rid of lerps?
What is a natural spray for psyllids?
How to get rid of psyllids naturally?
How do you care for African Mallow?
Adding a handful of perlite to regular store-bought potting soil should do the trick! African mallow is a fast growing plant and may deplete the nutrients in its soil over time. Replenish them with a gentle organic fertilizer or compost every 1-2 months depending on your location and season.
Is African Mallow easy to care for?
African mallow is generally considered an easy-to-care-for plant and makes a great choice for beginners! African mallow prefers for the soil to dry out between waterings and should be watered regularly.
Is tree mallow a good plant?
This lovely South African native has been a regional favorite for over a century. It is gaining popularity worldwide for its easy care, and continuous display of blooms through the growing season. The flowers look like miniature versions of Tree Mallow. A very charming plant and an excellent choice for growing in a container.
How do you grow African Mallow?
Fertilize more often during the growing season and in warmer and brighter climates. African mallow grows vertically and new growth will emerge from the top of the plant. African mallow can be grown outdoors in USDA Hardiness Zones 8a-11b. Find your local hardiness zone here . The seeds of African mallow can be used to grow new plants!