Western flower thrips (Frankliniella occidentalis). Close-up, immature thrips (left) and adults. Very much enlarged. Real size (0.9 to 1.1 mm) Ⓒ M. Billah, icipe
Close-up of Thrips (Megalurothrips sjostedti (black) and Frankliniella occidentalis (yellow). Real size (0.9 to 1.1 mm) Ⓒ GTZ-IPM Horticulture, Kenya
Thrips damage on tomato. Thrips are small (about 1 to 2 mm long) Ⓒ A.M. Varela, icipe
Thrips damage on lower leaf surface Ⓒ A.A. Seif, icipe
Thrips damage on bean pods Ⓒ A.M. Varela, icipe
Thrips on okra flower Ⓒ A.M. Varela, icipe
Adult and immature thrips (Thrips tabaci) (related species). Immatures (on top) are wingless and generally are light colored. Adults vary in color and have four wings lined with long hairs, it is about 1-1.5mm small. Ⓒ Courtesy EcoPort (http://www.ecoport.org): Alton N. Sparks, Jr., The University of Georgia
Thrips damage to flower buds on tomato Ⓒ A.M.Varela, icipe
Thrips damage to tomato leaflet Ⓒ A.M.Varela, icipe
Thrips and their feeding damage on tomato fruits. Note residues of pesticide applied seen as white marks. Ⓒ A.M.Varela, icipe
Thrips damage on passionfruit Ⓒ A.M. Varela, icipe
Thrips damage on eggplant Ⓒ A.M. Varela, icipe
Thrips damage on snowpea Ⓒ A.M. Varela, icipe
Thrips damage on a chilli pod Ⓒ A.A. Seif & B. Nyambo, icipe
Thrips on onion. Thrips are 1-1.5mm small. Ⓒ Whitney Cranshaw, Colorado State University, Bugwood.org Scientific Name
Thrips are tiny insects that can cause major damage to African mallow shrubs Left uncontrolled, thrips can weaken and even kill these ornamental plants Fortunately, there are several effective methods for getting rid of thrips and protecting your African mallow shrubs. This comprehensive guide will explore the best practices for identifying, treating, and preventing thrips infestations.
What Are Thrips?
Thrips are slender, winged insects measuring around 1/20th of an inch in length. They vary in color from yellowish to dark brown or black. Thrips have rasping, sucking mouthparts that they use to pierce plant tissues and feed on the sap
These tiny pests attack a wide variety of plants, including many ornamental shrubs like African mallow. Thrips feed mostly on new growth, flowers, and buds. An infestation can stunt plant growth, distort leaves and buds, and cause discoloration or scarring on foliage and petals. Left uncontrolled, thrips can seriously weaken and even kill African mallow shrubs.
Signs of a Thrips Infestation
It’s important to regularly inspect your African mallow shrubs for early signs of a thrips infestation. Here are some of the most common symptoms:
- Discolored, distorted leaves with brown scarring or silvered spots
- Stunted new growth and deformed buds or flowers
- Small black dots of fecal matter on leaves and petals
- White or tan-colored larvae on buds and flowers
- Increased leaf drop
If you spot any of these signs, take action right away to treat the infestation before major damage occurs.
Effective Thrips Treatments
When thrips are detected on your African mallow shrub, there are several effective treatment options available. Natural, non-toxic remedies are ideal for controlling thrips without harming beneficial garden insects.
Insecticidal Soap
Insecticidal soap is a natural pesticide that can safely eliminate thrips. It works by breaking down the pests’ protective outer layer and causing dehydration. Spray insecticidal soap directly on infested leaves, buds, and stems. Two or three applications spaced 7-10 days apart can eliminate an existing thrips population.
Neem Oil
Extracted from the neem tree, this organic oil kills thrips on contact by disrupting their hormones and ability to feed. Mix neem oil with water according to label directions and thoroughly coat all parts of the plant, including the undersides of leaves where thrips hide. Reapply every 1-2 weeks as needed.
Water Sprays
A strong spray of water can physically knock thrips off your African mallow shrub. Focus the spray on the undersides of leaves and inside flower buds where thrips tend to congregate. Repeat daily until you see a reduction in the pest numbers.
Beneficial Insects
Natural predators like ladybugs, lacewings, and predatory mites will feed on thrips. Attract these beneficial insects to your garden with companion plants. You can also purchase them from garden centers to release onto infested shrubs.
Preventative Thrips Control
Along with treatment, taking preventative measures is key to protecting your African mallow shrubs from recurring thrips infestations:
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Remove and destroy seriously infested branches and foliage.
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Disinfect your gardening tools regularly.
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Avoid excess nitrogen fertilization which promotes thrips growth.
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Install yellow sticky traps near plants to capture adult thrips.
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Cull nearby weeds and debris where thrips may breed.
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Use a row cover to create a physical barrier against the pests.
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Water shrubs at ground level to avoid moisture on leaves.
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Apply mulch to suppress weeds and retain soil moisture.
When to Call a Professional
In severe thrips infestations that persist despite treatment, contacting a professional may be warranted. Arborists and horticulturists have access to stronger insecticides that may be needed to fully eradicate the pests. They can also use specialized equipment to thoroughly spray tall, mature African mallow shrubs.
Left unchecked, thrips can seriously damage your beautiful African mallow shrubs. By learning to recognize the signs of infestation early, using organic remedies like insecticidal soap and neem oil, attracting beneficials, and taking preventative measures, you can successfully defeat this common garden pest. With prompt, thorough treatment and ongoing vigilance, your African mallow will thrive once again, rewarding you with vibrant flowers and lush, healthy foliage.
Major species of thrips attacking crops in Africa:
- African bean flower thrips (Megalurothrips sjostedti)
- Coffee thrips (Diarthrothrips coffeae)
- Blossom or Cotton bud thrips (Frankliniella schultzei)
- Black tea thrips (Heliothrips haemorrhoidales)
- Banana thrips (Hercinothrips bicinctus)
- Citrus thrips (Scirtothrips aurantii)
- Cacao or red banded thrips (Selenothrips rubrocinctus)
- Tomato thrips (Ceratothripoides brunneus)
- Cereal thrips (Haplothrips spp)
- Tea thrips (Scirtothrips kenyensis)
- Onion thrips (Thrips tabaci)
- Western flower thrips (Frankliniella occidentalis)
Thrips attack a wide number of vegetables, fruit and flower crops and cereals. Some species are specific to particular host plants while other feed on many host plants. Both onion thrips and western flower thrips attack a wide range of plants including cereals and broadleaved crops.
| Thrips damage on lower leaf surface |
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© A.A. Seif. icipe |
The characteristic symptom of attack is a silvery sheen of the attacked plant tissue, and white or silvery patches and streaks on leaves, fruits and pods. Affected tissue will dry up when the damage is severe. A further indicating of attack by thrips is small black spots of faecal material on the infested parts of the plant. However, small dark spots can also be observed on plants attacked by other insects such as lace bugs. Damaged leaves may become papery and distorted. Infested terminals lose their colour, roll, and drop leaves prematurely. Feeding on fruits leaves a roughened silvery texture on the skin.
Flowering stage, post-harvest, seedling stage and vegetative growing stage.
Growing points, inflorescence and leaves.
Biology and Ecology of Thrips
| Thrips on onion. Thrips are 1-1.5 mm small. |
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© Whitney Cranshaw, Colorado State University, Bugwood.org |
Eggs are very tiny. A single egg is 0.25 mm long and 0.1 mm wide. They are white when freshly laid and turn pale yellow toward maturation. Eggs are usually laid singly inside the plant tissue, and are therefore not visible. Some thrips (e.g. Haplothrips spp) lay eggs singly or in clusters attached to the plant surface.
Larvae. The first and second instar larvae are very small (0.5 to 1.2 mm), elongated, slender, and vary in colour from pale-yellow, orange or red according to the species. They have piercing-sucking mouthparts. They resemble a miniature version of the adults but do not have wings.
Pre pupa and pupae. These two or three instars are intermediate forms between the nymph and the adult. They have short wing buds but no functional wings. During these stages thrips are inactive and do not feed and therefore they do not do cause any damage to the plant. Pupation may occur on a plant or in the soil beneath, depending on species.
| Close-up of thrips (Megalurothrips sjostedti (black) andFrankliniella occidentalis (yellow). Real size 1 to 1.5 mm. |
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© A. M. Varela, icipe |
Adult thrips are small (usually 1 to 1.5 mm), slender and usually winged. The wings are long, narrow and fringed with long hairs, and at rest, are tied on the back along the body. Their colour varies according to the species. Most species are black, brown or yellow
| Thrips life cycle |
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© A.M. Varela, icipe |
The life cycle takes about two to three weeks under warm conditions, which gives them a enormous capacity for increase. Thrips migrate actively between different hosts.
THRIPS?! How to kill thrips and save your grow.
FAQ
How to get rid of thrips on African violet?
What is the easiest way to get rid of thrips?
What is the best control for thrips?
How do you know if African violets have thrips?
How do you get rid of thrips on Hibiscus plants?
Soap and Water A quick and easy home remedy to get rid of thrips on monstera, roses, hibiscus, orchids, tomatoes, and other plants is soap and water. Dilute 5 tablespoons of liquid dish soap in a gallon of water. Shake well and spray the homemade solution all over indoor or greenhouse plants.
How do you get rid of thrips on plants?
Mix 1 or 2 tbsp. of liquid Castile soap in a gallon (4 l) of distilled warm water. Pour the mixture into a spray bottle and liberally douse both sides of the leaves to help kill off the thrips. Alternatively, you can buy a commercial insecticidal soap to treat your houseplants. Use once a week for the best results.
Do thrips kill plants?
Thrips are tiny, winged insects that do tremendous damage to plants. These common pests feed on the sap and juices of houseplants, garden plants, and greenhouse crops. Thrip infestations can damage plants so much that leaves lose color, and plants eventually die. Thrips are challenging to get rid of.
How to prevent thrips from taking over a plant?
Making use of your vacuum is a smart way to prevent thrips from taking over. The critters are so lightweight that gusts of wind transport them from plant to plant. Therefore, it is relatively easy to remove them with a vacuum cleaner that will suction them into a disposable dust bag.