Thrips are tiny insects that can cause major damage to plants in your garden or home. These tiny pests are barely visible to the naked eye, but the scars they leave behind on flowers, leaves, and fruits are all too easy to spot. Thrips use their mouths to puncture plant cells and feed on the fluids inside, leaving behind streaks of pale or discolored plant tissue. An infestation can stunt plant growth, deform and drop buds and leaves, and seriously mar the appearance of prized plants.

Thrips may also spread harmful plant viruses as they feed. So taking action to control thrips is important to protect your plants. The good news is that with persistence and an integrated approach, you can get thrips under control and keep them from destroying your plants.

Identifying Thrips and Their Damage

The first step in thrips control is learning to identify the pests and the symptoms of their damage. There are thousands of different thrips species, but they share some common characteristics that can help you spot an infestation.

Adult thrips are very small, slender insects, around 1-2 millimeters in length. Their bodies are elongated and tubular, often brownish or blackish in color. Thrips have two pairs of narrow, fringed wings. Nymphs are smaller and wingless, but similar in appearance to the adults.

Thrips damage manifests in several ways:

• Brown or silvery scarring, streaks, and patches on leaves, flowers, and fruits
• Distorted, curled leaves and deformed buds or fruits
• Stunted or wilted shoots
• Discolored blossoms and premature bud or flower drop
• Black dots of thrips excrement on foliage

Thrips tend to gather in protected places like unopened buds, crevices, and on the undersides of leaves. So you may need to look closely to spot the insects themselves.

To check for thrips, try shaking a branch or plant over a sheet of white paper. This will dislodge thrips so you can see them against the white background. Inspect the paper closely with a magnifying glass. Set out sticky traps around susceptible plants. Blue sticky traps are especially effective for monitoring thrips.

Thrips favor flowering plants, vegetables, and many common trees and shrubs. Some of the most susceptible plants include:

• Fruit trees - apple, citrus, stone fruits
• Ornamentals - roses, dogwood, magnolia, rhododendron
• Vegetables - onions, beans, carrots, squash
• Herbs - mint, oregano, basil
• Houseplants - palms, dracaena, monstera

Regularly inspect these and other vulnerable plants to allow early detection and treatment of thrips. The sooner you catch an infestation, the easier it will be to get under control.

Controlling Thrips on Plants

Thrips can be challenging to manage, but employing multiple control tactics at the same time provides the best chance of protecting your plants. Focus first on less-toxic cultural and mechanical controls, turning to insecticides only if needed for severe infestations.

Sanitation - The simplest thrips control method is to remove and destroy seriously infested plant parts. Prune off affected leaves, flowers, stems and fruits and place in sealed bags in the trash, not the compost pile. Eliminating thrips hiding places deprives them of food and breeding sites.

Keep the garden free of weeds and clear of spent plants after the growing season. Thrips seek shelter in cracks, under bark, and in leaf litter when not feeding on plants. Sanitation cuts down on areas where thrips can survive winter and launch new attacks come spring.

Water spray - Thrips dislike moisture and a forceful spray of water can help wash away and even kill adults and larvae on plants. Focus the spray on the undersides of leaves and where branches meet stems. Repeat sprayings may be needed to control thrips through their life cycle.

Beneficial insects - Certain predatory insects like minute pirate bugs, lacewings, and predatory mites will feed on thrips. You can buy them from garden centers or attract them naturally by growing diverse flowering plants. Let beneficial insects do part of the work of controlling thrips for you. But don't use broad-spectrum insecticides that will also kill the good bugs!

Reflective mulch - Spreading silver reflective mulch around plants can help deter thrips from finding and landing on them. The reflected light confuses the pests. This works best for smaller plants and likely provides only temporary thrips relief.

Insecticidal soap - Insecticidal soaps made from plant oils will kill thrips on contact with no toxic residue. Use a spray bottle to coat the undersides of leaves paying special attention to the bases of leaves and stems where thrips gather. Reapply every 5-7 days as needed to control hatching larvae.

Neem oil - Extracted from the seeds of the neem tree, neem oil disrupts the hormonal systems of insects, deterring them from feeding and mating. Though it acts more slowly than soap, neem oil offers residual control, preventing larvae from maturing into adults.

Pyrethrin insecticide - For severe thrips infestations, a targeted application of pyrethrin may be warranted. Derived from chrysanthemums, pyrethrin provides quick knock-down of thrips populations. To prevent rebound, follow up with thorough sanitation and introduction of predatory insects.

Spot treat only affected areas of plants rather than blanketing everything with insecticide. And be sure to read and follow all label directions to minimize risks to yourself, beneficials, wildlife, and the environment.

Preventing Thrips from Damaging Plants

An ounce of prevention is truly worth a pound of cure when it comes to pesky thrips. Here are some effective ways to stop thrips before they get established and cause harm to your plants:

• Carefully inspect all new plants before bringing them home. Quarantine any suspicious plants away from the rest of the garden for a few weeks to ensure they are pest-free.

• Space plants appropriately to allow for good airflow. Avoid overcrowding.

• Water and fertilize plants properly to keep them vigorous. Healthy plants can better withstand pest attacks. But don't overdo the fertilizer which can stimulate excess new growth that attracts thrips.

• Remove weeds, alternate insect food sources, from around the garden.

• Check susceptible plants frequently and be on the lookout for early signs of thrips like distorted growth. Catching infestations early makes control much easier.

• Use row covers to exclude thrips from getting to young vegetable seedlings and transplants.

• Interplant onions, garlic, and other pungent herbs to help repel thrips.

• Remove spent flowers and vegetables promptly after harvest. Don't give thrips places to hide and overwinter.

With quick identification, persistence, and varied control methods you can minimize damage from troublesome thrips. Protect the beauty and productivity of your plants this growing season by implementing effective thrips control practices. Stay vigilant in checking for pests and be prepared to take prompt action at the first sign of damage.

Frequently Asked Questions About Controlling Thrips

How do I know if I have thrips?

Look for signs of damage - scarring, discoloration, and deformities on leaves, flowers, and fruits. Shake foliage over white paper to dislodge thrips for closer inspection. Set out blue sticky traps to catch adults. Thrips excrement may appear as black speckles on plant parts.

What insects eat thrips?

Many beneficial predatory insects like minute pirate bugs, predatory mites, and lacewings will feed on thrips. Avoid insecticides that would harm populations of these natural pest controllers.

Are thrips harmful to humans?

Thrips do not bite people, pets, or wildlife. They are solely plant pests, though they can spread plant viruses. Their damage is cosmetic rather than threatening to human health.

What plants do thrips dislike?

Thrips are repelled by plants with strong scents like onions, garlic, and mint. Interplant these around flowers and vegetables susceptible to thrips.

Will insecticidal soap kill thrips?

Yes, insecticidal soap will kill thrips on contact through its suffocating mode of action. Good coverage of leaf undersides is important for best results. Repeat applications may be needed.

Can neem oil get rid of thrips?

Neem oil is effective for thrips control, though it may take several days to act. It works by disrupting insect hormones to prevent larvae from maturing. Neem oil offers residual activity to provide control between applications.

How soon after spraying will thrips die?

With contact insecticides like soaps and pyrethrins, thrips die within minutes to hours after being sprayed. Systemic insecticides usually take 24-48 hours to fully kill thrips feeding on treated plants. Always follow label directions.

How often should I spray for thrips?

For contact insecticides, repeat applications every 5-7 days while thrips are active. For systemic and residual products, spacing of 7-14 days is often sufficient. Monitor plants and adjust frequency based on presence of new damage.

What can I spray on vegetables for thrips?

Stick to insecticidal soaps, neem oil, or pyrethrin on edible plants. For best results alternate between these to disrupt thrips generations. Always follow label guidelines for permitted food uses.

Will thrips come back after spraying?

Thrips can reinfest plants from nearby weeds or gardens. Their small size and prolific reproduction makes thrips difficult to eradicate fully. Maintain control with repeated applications of organic insecticides combined with vigilant garden sanitation.

The Bottom Line on Controlling Thrips

Dealing with destructive thrips takes persistence and an integrated pest management plan. No single method will provide complete control on its own. The best results come from combining sanitation practices, physical barriers, biological control, and least-toxic insecticides applied only as needed.

Monitor plants closely to detect thrips early before populations explode. Remove infested plant parts immediately and dispose of properly. Regular applications of insecticidal soaps or neem oil knock back thrips so they cannot multiply. Maintain biological control by attracting predator insects. Keep the garden free of litter and weeds where thrips find shelter.

With time and dedication, you can minimize plant damage from troublesome thrips. Pay close attention to vulnerable plants and be prepared to take prompt control action at the first signs of infestation. Your efforts will pay off with healthy, productive, and beautiful plants this growing season.