Did you know there are over 6,000 species of thrips in the world? And they’re all fond of feeding on your houseplants. The best way to get rid of them is to prevent them in the first place.
It would be best to act fast once you find thrips on your houseplants. They damage plants over time by ingesting their juices. It’s a slow, painful process – and you won’t even see it until it’s too late.
You can use many strategies to get rid of thrips on houseplants. Just ensure you’re dealing with thrips and not some other pest that looks similar.
Thrips can easily spread from one houseplant to another. This is how they propagate their colonies throughout your indoor garden.
Your priority is to isolate the infested houseplant to contain the infestation. If you think quarantining is an extreme step, you may prune visibly damaged leaves.
Affected leaves will show signs of wrinkling and honeydew residue. They may also have the presence of dark fecal matter.
Start pruning right away to discard the affected leaves. Some houseplants in California may be too far gone and cannot be rescued.
In this case, it may be best to remove them entirely to contain the infestation. It’s a tough decision that will ultimately save your indoor garden.
It is recommended to draw a schedule to routinely inspect your plants for thrip colonies. This should help you identify infestations at an early stage.
As a rule of thumb, always quarantine new houseplants before introducing them to your garden.
For this step, take your houseplants outside. You can also keep them indoors if you’re not afraid of making a mess.
Use a water hose to blast the leaves to evict them forcefully. Don’t forget to focus on the underside of the leaves. You can also use a soapy solution to get rid of the bugs.
Mix two tablespoons of detergent in 4 liters of water. Pour some of the mixtures into a spray bottle. Now apply the mixture as many times as needed until you get rid of them on your house plant.
You can use natural pesticides that repel insects but don’t damage plants. Try not to use industry-grade pesticides because they can easily damage your house plants.
This section will explore natural pesticides that you can prepare at home to save money.
Note: Most insecticides listed below are very safe for plants. Test their reaction to the insecticide before applying it on a large scale.
Lightly mist a small part of the plant with the insecticide. Observe the plant’s reaction for a few hours. Stop using the insecticide if this leads to an adverse reaction.
Neem oil is a naturally occurring insecticide found in the seed of the neem tree. It is among the most effective insecticides for controlling thrips.
Neem oil should be your first line of attack against thrips before using harsher methods. The insecticide does not harm your plants and can be prepared at home.
You will need the following ingredients:
- Dishwashing Soap
- 4 liters of water
- Neem oil
Toss all the ingredients into a container making sure to mix them thoroughly. Spray the mixture directly on affected plants and leaves.
This will create undesirable conditions for thrips, forcing them to leave. The best part is that neem oil doesn’t harm predatory insects like ladybugs.
Peppermint spray has a powerful odor that can repel thrips. It can also make life unbearable for female adults who will not lay eggs.
You can prepare a peppermint spray mixture at home. Here are the ingredients you will need:
- Five drops of dish soap
- 4 liters of water
- 20 drops of peppermint oil
Mix all of the ingredients in a container. Now you have a few weeks’ worth of peppermint spray.
Lightly mist infested plants with peppermint spray once every week until the infestation clears. You may increase the application frequency depending on the infestation’s severity.
The best time to apply peppermint spray is in the morning or evening. You may add other essential oils such as rosemary and thyme to the solution.
Rosemary oil is a potent herbal pesticide that gardeners use for indoor houseplants. It is a safe alternative to chemicals and can deter thrips.
Here’s how you can prepare the mixture:
- Place 110 grams of rosemary in a clear glass jar
- Pour safflower oil to cover the rosemary
- Close the jar and place it in a warm, sunny area for 48 hours
- Now open the jar and pass the soil through a strainer into a measuring cup
- Discard what’s left of the herbs.
- Add 100 grams of liquid soap
- Add 1 cup of water
Pour the mixture into a spray bottle. Now lightly mist your plants with the mixture. Keep the bottle at least one foot away from the pants.
Pyrethrin is an organic insecticide that work well on thrips. They are very popular among plant growers because of their toxins.
Pyrethrin insecticides contain nerve toxins that will kill soft-bodied pests like thrips. They are non-toxic to plants, humans, and animals in low doses.
Your shampoo is likely to contain pyrethrin for pest and lice control.
It is recommended to spray infected plants with pyrethrin once every three days. Use two applications of the insecticide. This should take care of any serious infestations.
Always use a pure pyrethrin pesticide, which is considered organic and safe. Do not use pyrethroid pesticide because it contains additives that may harm your plant.
Hydrogen peroxide can be deadly to plants in high doses. It should be reserved when nothing else seems to be working.
Hydrogen peroxide may boost your plant’s growth in small doses. This is because it contains oxygen molecules that plants can use.
You can prepare a diluted mixture of hydrogen peroxide solution at home. Mix 3 tablespoons of 3% hydrogen peroxide solution into 1 gallon of water.
This is a four-week supply of diluted hydrogen peroxide. Now gently mist plant leaves with the hydrogen peroxide solution. You may increase the chemical concentration depending on the infestation’s severity.
A fool-proof option to control thrip infestation is to deploy predator bugs. Let’s take a look at popular predator bugs.
Most plant growers agree that the best thrip predator is Cucumeris.
These tan colored mites live on the underside of leaves. They are effective against both thrips and spider mites if applied at an early stage.
They have a lifespan of about 12 days. Female adults will lay three eggs per day. This amounts to about 40 eggs throughout their life.
They lay eggs on the lower surface of leaves. It takes about three days for the eggs to hatch. Newly hatched nymphs won’t feed until they molt.
They will feed for a week until becoming adults. An adult cucumeris will live for up to one month and eat one thrip daily. This means that the predator is most effective when the population of thrips is low.
Note that plants with hairy leaves may affect the performance of cucumeris mites. This is because it becomes harder for the mites to move around the plant.
Ladybugs are an excellent choice for killing thrips. They have a voracious appetite and will go on a feeding frenzy in no time. A single ladybug can eat dozens of thrips in a single hour.
Make sure to mist your houseplants with some water when releasing the ladybugs. This will provide them with some water to drink before they start feeding.
Although lacewings mostly feed on nectar, their larvae thrive on eating pests such as thrips. They can eat up to 300 presets, making them ideal for cleaning heavy infestations.
Besides eating thrips, lacewings like to eat spider mites, mealybugs, and aphids. In other words, lacewings are one of the most effective predators.
Chemical pesticides should be used when mild insecticides fail to control thrip colonies.
Thrips are extremely small and may go undetected for weeks until you notice plant damage. They are only 1/20th of an inch with the diameter of a sewing needle.
Despite having very short lives, thrips reproduce at an incredibly fast pace. Thrips may have up to 15 overlapping generations in a single season.
Female adults prefer to lay their eggs when the climate is still warm in springtime. The eggs readily hatch after about five days.
Nymph thrips are voracious eaters with insatiable appetites that can last for several weeks. If they have their way, your healthy plants will wilt.
These minute pests vary in color with small wings. This makes it hard to detect them unless they swarm your plant in large numbers.
The first thing you will notice is thrip damage, unless you routinely inspect your plant. The following signs are consistent with thrip infestation:
- Papery leaves that look like they are hollow from the inside
- Clumps of silver streaks forming on the foliage
- Powdery mildew on the leaves
Pro tip: Use sticky traps to identify the thrip infestation. Sticky traps can also help you monitor the severity of the infestation. Sticky traps will not eliminate thrips. It only confirms the infestation.
The exact symptoms of thrip infestation depend on the type of plant involved. Unfortunately, thrips carry diseases with them that they transmit to the plants.
This makes their infestation more deadly to plants. Diseased plants will have the following symptoms:
- A visible change in color
- Black spots
- Downy mildew
- Lack of growth
- Leaves falling
Some plant growers confuse thrip damage with aphid damage. Both pests leave a honeydew residue that leads to mildew.
However, aphids have a very distinct appearance. They have oval bodies while thrips have long and skinny structures. You are encouraged to use a magnifying glass to identify them.
The same plant can be affected by both aphids and thrips. Fortunately, you can use the above preventive methods to eliminate their invasion.
It is best to deploy prevention methods to ward off thrip infestation. Your goal is to make your houseplants less desirable for thrips.
For starters, thrips are attracted to bright colors. They are drawn to white, blue, and yellow. You can use sticky traps in these colors to trap them.
The best way to prevent thrip infestation is to trap females before they lay eggs.
Finally, you should always quarantine new houseplants before adding them to your indoor garden. Plants that are infected should be either treated or removed in worst-case scenarios.
Let’s take a look at thrip prevention methods that are proven to be effective.
Plants that are under water stress are susceptible to a thrip infestation. This is why you should stick to a strict schedule for hydrating your plants.
This also means fixing the soil if it is in disrepair. Plants draw water from the soil for nourishment. So if the foundation is in disarray, the plant will be dehydrated.
It is important to remove plants that have died or are yellowing. They may be beyond rescue at this point.
They are organic matter that will be preyed upon by thrips and other pests. Weaker leaves may be removed manually. Try not to apply excessive force when removing the leaf.
If the leaf resists you, it’s probably still clinging to life. Instead, prune away leaves that are too weak.
So there you have it, an in-depth guide on how to get rid of thrips. The methods discussed above may be used with other pests such as mealybugs and aphids.
We recommend using natural pesticides before resorting to harsh chemicals. Always prioritize preventive methods to keep pests at bay. So how do you clear thrip infestation from your plants?
You may like the following houseplant articles:
- How to Identify Thrips on Houseplants
- Best Potting Soil for Houseplants
- How to Get Rid of Scale on Houseplants
- Are Eggshells Good for Houseplants?
- How to Kill Spider Mites on Houseplants?
Hi! I’m Sophia, and I love plants – especially an expert in growing house plants. I stay in Chicago, United States of America, and through my blog and social media platforms, provide tips and tricks on how to grow healthy, vibrant plants indoors. Check out more here.