What are thrips?
Thrips (Thysanoptera), also known as fringe-winged beetles, are pests that mainly attack houseplants. Since they feed on plant sap, they can cause considerable damage to the plants.
How to identify thrips
The tiny insects, up to three millimeters in size, are yellow to dark brown in color. The adults have striped, narrow wings on their backs. Their larvae look like small yellow, light green or whitish worms and are usually found in the soil or on the undersides of leaves. Since thrips are difficult to see with the naked eye due to their size, an infestation is usually only apparent when the plant looks sickly.
damage to the plant
Silvery, white spots on the upper side of the leaves and on the flowers indicate a thrips infestation. In addition to the sucking marks, tiny brown dots, the insects' excretions and the light-colored larvae can often be seen on the underside of the leaves. Infected plants often show growth disorders and new leaves look deformed. The removal of plant sap and nutrients significantly weakens the affected plants, which in the worst case can lead to the death of the plant.
Fighting thrips: effective measures that really help
- Isolate the plant : Infected plants should be separated from others to prevent the spread. Thrips do not tolerate damp and cool conditions well - if the weather is right, you can also temporarily place the plant on the balcony or terrace.
- Showering : Rinse the plant thoroughly with cold water. Cover the surface with cling film or a plastic bag to prevent the pests or larvae from being washed into the substrate.
- Replace the substrate : Since the thrips larvae often live in the soil, the soil should be renewed to prevent spread.
- Spraying : There are various natural remedies for thrips that you can use to spray the plant regularly to get rid of the thrips.
Home Remedies Against Thrips
- Neem oil : Mix a tablespoon of neem oil with water and spray the plant thoroughly, especially the underside of the leaves. Alternatively, you can dab the larvae directly with a few drops of neem oil.
- Olive oil and dishwashing liquid: Take a liter of lukewarm water, add two tablespoons of olive oil and a few drops of dishwashing liquid and spray the plants with the mixture twice a week.
- Soap : Alternatively, mix a solution of water and soft soap and spray the plant thoroughly.
Natural enemies: beneficial organisms against thrips
The use of beneficial organisms is an environmentally friendly method of controlling thrips. Predatory mites, nematodes and lacewing larvae have proven to be particularly helpful against thrips infestation, as they specifically eat the pests and their larvae.
blue signs against thrips
Blue-colored sticky boards are an effective addition to infestation reduction, primarily in combination with other control methods. Thrips are attracted to the blue color, stick to the boards and die.
Thrips on Monstera, Orchids and Co.: These plants are particularly susceptible
Houseplants such as Monstera , Calathea, fiddle leaf fig (Ficus lyrata) and orchids are among the species particularly susceptible to thrips infestation. Other ornamental plants such as palms or poinsettias are also frequently affected. Regular checks of these plants are important in order to detect and combat infestation at an early stage.
Preventing Thrips Infestation
Thrips can be spread by wind or introduced via potting soil. Although an infestation cannot be completely avoided, there are some tips to prevent an infestation:
- Increase humidity : Since thrips feel particularly comfortable in dry heat, you can increase the humidity by regularly spraying the plants with water.
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Regular checks : Plants should be checked regularly for signs of infestation, especially in summer and at the beginning of the heating season.
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Use neem oil preventively : The oil is known for its insecticidal effect and helps to keep thrips away as a preventative measure. You can therefore regularly spray your plants with a neem oil mixture.
