Thrips infestation can go undetected until there is an overwhelming presence, damaging leaves and buds. Check for dark specks on the undersides of leaves as well as abnormal growth patterns to detect this pest.
Spray your houseplants with insecticidal soap, neem oil or soapy water to kill insects and disrupt their life cycles. Be sure to thoroughly spray all parts of the plant – including its undersides and flowers.
Insecticidal Soap
Soap has long been utilized as an insecticide. It works to eliminate thrips by cutting through their outer coating and disrupting internal membranes; once dehydrated and dead, they dehydrate further before becoming visible damage on leaves, flowers or fruit – often manifested by silvery or brownish spots on foliage, flowers and fruit as well as dropping dark deposits that look similar to coffee grounds – likely just their excrement!
Apply a mixture of soap and water using a spray bottle on outdoor plants to the undersides of leaves where thrips gathers, particularly the undersides where they collect. The spray will wash thrips off but won’t stop their return; use caution!
Insecticidal soaps can be an effective defense against many pests, including thrips. Simply mix equal parts of mild liquid dish soap and water in a spray bottle and apply to infested leaves, flowers and fruit of infested plants every four to seven days until all thrips infestation has cleared away. As some plants such as ferns and succulents may be sensitive to insecticidal soap sprays (ferns/succulents are particularly sensitive), test on several leaves first before spraying everything!
Some gardeners opt for natural alternatives such as neem oil. A few teaspoons mixed into one gallon of water will provide sufficient coverage against harmful bugs like thrips and white fly, without harming beneficial bees or any other beneficial insects.
Neem oil is a natural product derived from the neem tree and works by blocking hormones that trigger insects to feed or reproduce, providing a safer alternative to synthetic pesticides like pyrethroid pesticides that contain dangerous pyrethroid compounds and can harm bees and other pollinators.
Pyrethrin, an organic substance derived from chrysanthemums, can also be an effective defense against thrips infestation. A diluted solution using 4 teaspoons of neem oil and 2 teaspoons of dish soap per gallon of water should be applied topically over infested plants to spray off potential infestation. Repeat every 4-7 days until you see improvement.
Overfertilizing your garden, lawn or trees with nitrogen could increase thrips numbers. A high nitrogen level in soil also promotes weed growth that competes for nutrients with plants for sustenance – thus diminishing their health and potentially decreasing health benefits of those plantings.
Check your houseplants for thrips by placing a sheet of light-colored paper under their flowers and leaves, gently shaking it over them, and looking at any thrips that fall onto it. This method is especially helpful in monitoring thrips that feed on buds or unexpanded shoot tips; alternatively you could also use sticky traps.
Systemic Insecticide
Thrips pests have a lengthy lifecycle that makes elimination more challenging than expected. Once eggs hatch out they rapidly mature into adult flies that fly back up to your plants and repeat their cycle of destruction. Luckily there are ways to prevent thrips infestation and protect indoor plants.
One of the most crucial steps when purchasing new plants from nurseries or unfamiliar sources, such as unknown infestation, is quarantining them for two to three weeks after purchasing. This will prevent spreading thrips to other houseplants. If there are heavily infested plants you can use mild insecticidal soap as a form of control if necessary – yellow sticky traps may also prove helpful in monitoring them and catching adult thrips when they appear on plants.
Bonide Systemic can also help you eliminate severe infestations of thrips in houseplants and garden plants by being absorbed through their roots into specific parts where thrips is found, making sure it kills when they attempt to suckle plant juices from these areas.
These products may be more costly and time-consuming to use, but can be extremely effective against thrips. Apply the product multiple times every few weeks for best results.
Another effective strategy for protecting indoor plants against insect problems is using natural insecticides like pyrethrins from chrysanthemums or neem oil as natural insecticides, using the recommended spray volume for your specific plant species. Since these sprays do not harm pollinators or beneficial insects, they’re safe choices that won’t harm beneficial insects or pollinators – just make sure you apply them when the flowers and pollen have not yet bloomed so as to not kill the flowers or pollen from blooming flowers and pollen!
Yellow Sticky Traps
Yellow sticky traps attract many pest insects that attack houseplants. Yellow traps attract thrips and other flying insect pests like fungus gnats and whiteflies which could be attacking your plants nearby. Similar blue versions also exist; however, these may be less effective at attracting certain types of pests.
Yellow traps can be an easy and efficient way to monitor thrips and other pests on houseplants. Simply place clear double-sided sticky tape, commonly sold at stationery stores, near the base of your plant in its growing media near its root system and label each trap with an indicator tag or flag so you can easily recognize and locate them later on. Replace tapes at regular intervals – typically weekly.
Young thrips larvae feed within the surface layers of leaves, flower petals and stems. Some species go through one to two larval stages while others have up to five. When their development reaches completion they cease feeding and fall off to pupate – greenhouse thrips and Laurel thrips often leave behind pupal skins while mousehole tree and avocado thrips create galls in plant stems or distort terminals with galls.
Once thrips have pupated, their adults emerge with wings and begin flying away from the plant they infected. As adults flit about, thrips lay eggs beneath leaves or elsewhere on the plant where they settle to lay more eggs – damaging leaves or flowers while altering their shape in general.
Thrips pests tend to target vegetable crops such as onions, garlic and peppers; however they can also invade houseplants like gladiolus, impatiens and petunia as well as woody ornamentals like rose and lilyturf as well as stone fruit trees. Thrips can easily be distinguished from other pests due to their yellow to orangish colors with bristle-like hairs at their abdomen tips – they make these insects easy to identify from other types of insects!
Blue Sticky Traps
Utilizing blue sticky traps to monitor thrips populations can be an effective strategy in both open field and greenhouse cropping environments. Their bright blue hue attracts thrips while their sticky glue trapping keeps them trapped until they die, giving growers an accurate picture of population trends. They can be used alone or combined with other trapping techniques for maximum effectiveness; multiple traps in a canopy may provide more accurate assessments of abundance and help identify when damage thresholds have been reached; for instance in strawberry crops grown in the UK the risk begins once numbers exceed four per flower without predator establishment.
Different color lures are available for use in blue traps to attract various species of thrips. Some species, like western flower thrips (WFT), respond better to WFT aggregation pheromone while others respond better to more general-attractant kairomones. Aside from lure color and shape considerations, trap design also plays a part in its effectiveness – a funnel-shaped body trap is better at catching WFT than an egg-shaped body trap.
A randomized blocks design was employed to assess the performance of colored traps in a mango agroecosystem. Twenty mango inflorescences were collected on each sampling date either directly from traps or directly from the field and counted for their number of thrips; relationships were assessed between density on traps and inflorescences, counted thrips counted per inflorescence and inflorescence counted.
Results demonstrated that trap color did not significantly impact thrips density in inflorescences, but did influence trap density. Green, orange, and yellow traps caught higher numbers of natural enemies compared with blue, purple, and white traps; however, their high capture rates for thrips did not significantly reduce insect pollinator capture rates.
Notably, traps also had only a weak and non-significant correlation with inflorescences for measuring thrips density; thus demonstrating that looking at inflorescences is more useful in monitoring than using traps. These low and non-significant relationships may be due to highly variable populations throughout mango’s flowering season that made accurate comparisons difficult.
