Known for its signature smell and flavor, mint is one of the most popular herbs you can grow in your home. But as well as attracting legions of gardeners, mint can also attract unwanted attention from several devastating pests.
Mint is a vulnerable herb, and sadly if left unchecked, it doesn’t stand much of a chance. But don’t worry – I’m here to help.
With no natural defenses, mint is a vulnerable herb that falls prey to several common pests including mealybugs, spider mites, and thrips. Left unchecked, infestations can ruin your plant beyond repair. But with regular checks, diagnosing the culprit early, and ensuring the plant is receiving the best care, the mint plant can be protected throughout the growing season and beyond.
Today I am going to show you just how easy it is to defend your precious mint. From diagnosing the culprits to finding out the appropriate solutions, I’ll talk you through every step you need to take for your mint to achieve its potential.
Common Bugs on Mint And How to Get Rid of Them
Mealybugs are one of the most common pests that your mint plant will face. Thankfully, they are easy to spot, as their fluffy white appearance makes them hard to miss.
Mealybugs bite both leaves and stems and suck out their juices – your plant will have stunted growth, and discolored leaves which will droop and fall early.
An easy way of dealing with mealybugs is applying soapy water or rubbing alcohol to affected areas with a cotton bud. Allow it to sit for a few hours, before washing clean off.
Neem oil is also very effective on mealybugs as it suffocates adult bugs, and can also be used to prevent larvae from maturing.
If you see yellow or brown spots appearing throughout your mint plant’s leaves, you may have a spider mite infestation.
There are several species of mite, but the main culprit who feeds off mint is the two-spotted spider mite. These live on the underside of leaves and are especially attracted to new plant growth.
These spider mites thrive in dry, arid conditions, where they spin thin, frayed webbing throughout the leaves. Chances are if your plant has spider mites, it is also suffering from underwatering, too.
Dealing with spider mites is thankfully quite straightforward. Neem oil is a natural miticide, a chemical agent especially effective at killing mite infestations. You can also apply rubbing alcohol to affected areas of your plant, too.
Another solution to solving your spider mite problem is by increasing your watering frequency. As these pests thrive under dry, arid conditions, wetting your mint plant and ensuring the soil is moist will help their numbers at bay.
Named after for how they move their bodies, loopers are leaf-eating caterpillars that have an insatiable appetite for new growth, including new leaves and young stems. They love eating strong-smelling plants, which makes your mint a prime target.
If you spot holes or bite marks throughout your plant, or what looks to be cocoon shedding, you may well have a looper infestation. Thankfully, they are quite easy to see with the naked eye, so checking your plant for infestations regularly is a great way of catching them before they cause too much trouble.
Firstly, depending on the severity, you may be able to remove all the loopers by hand. Place the loopers in a bucket of soapy water to dispose of them. You should also look out for eggs (usually on the underside of leaves).
You can also use an insecticide that contains Bacillus thuringiensis, which is toxic to some insects, especially caterpillars, without harming other beneficial wildlife. Pepper spray is also effective, as caterpillars don’t appreciate the heat or strong smell.
Flea beetles are dark-colored, shiny-backed beetles that are famous for jumping high like fleas. They cause serious damage to plant leaves, including creating holes and striping new leaves of their vibrancy. Additionally, flea beetles can carry diseases such as blight, so it’s crucial you get a hand on their presence.
Lucky for you, the flea beetles jumping can also be their weakness, as sticky traps are an effective way of luring adult beetles away from plants and stopping them in their tracks. Additionally, because flea beetles are soft-bodied, they are extremely vulnerable to solutions such as neem oil or soapy water.
Aphids (Peach aphid)
Despite their name, peach aphids are small green or yellow insects that live on the underside of your mint’s leaves. Aphids bite into leaves and suck their juices out. Signs you have an aphid problem include damaged leaves, distorted color, spotting, and stunted growth.
Aphids are known to spread rapidly and can lead to devastating infestations if left unchecked.
Depending on the severity of your aphid problem, there are two avenues of treatment. If the infestation is small and contained, you can prune the affected leaves off the plant, or spray the aphids with water to knock them off.
However, if there is a high level of aphids, you may need to use an insecticidal soapy spray that stripes the insect of their cell membranes. You can also use an oily solution, which smothers them.
Cutworms are aptly named pests because they literally cut through your plants as they feed. As the larvae form of moths, cutworms are especially devastating for mint given how delicate and vulnerable it is.
A sure sign you have an infestation are cuts and holes throughout your mint, as well as spotting small caterpillar-like insects at the base of plants during the evening time.
There are a few treatments you can rely on to rid your mint of cutworms. The first is by manual power – picking them off your plant.
As cutworms are dormant during the day, the best time to strike is at night time when they are most active. Don a pair of gloves and remove pests as you discover them. Drop them in a bucket of soapy water to kill them.
Another treatment to consider is using diatomaceous earth, which dehydrates any insect that walks through it. Simply create a protective barrier around the base of your mint plant.
Similar to aphids, thrips are pesky pests that bite into the mint’s leaves and sucks their juices out. They’re even more annoying given they have small wings. A sure sign you have an infestation of thrips is leaf spotting and streaking, and leaves shriveling and curling inward.
One of the most effective treatments for any flying pest, including thrips, is the natural bug spray pyrethrin. Pyrethrin affects a thrip’s nervous system, paralyzing them and killing them in contact. Apply directly to infested areas to kill insects and repel breeding.
If your mint plant has long, thin caterpillars with white tendrils growing from their bodies, you have yourself a hairy caterpillar infestation. These caterpillars are notoriously hungry and will cause early defoliation of plants, i.e. leaf loss if left unchecked.
Additionally, they’re quite painful if you happen to touch them accidentally, making pruning and harvesting your mint extra troublesome.
Similar to cutworms, manually removing hairy caterpillars and their cocoons is an effective treatment. Remove them with tweezers and place them in a bucket of soapy water to kill them.
Another effective treatment is using an insecticide that contains Bacillus thuringiensis, which is proving to be an effective toxin to some insects, especially caterpillars and troublesome larvae.
Root-lesion nematodes are microscopic pests that cause a nutrient-deficient appearance to your mint plant. If it looks worse for wear despite your constant attention, then it may be time to investigate if root-lesion nematodes are present in your soil. (Source: ScienceDirect)
So how can you spot a microscopic pest? Unfortunately, this is one of the harder pests to diagnose effectively. Examine your mint’s root system.
If your plant has smaller, feeder roots, fraying edges or the root system as a whole is significantly underdeveloped, this may point towards root-lesion nematode.
Because this pest continues to attack plants until they die, time is crucial to your mint’s recovery. The first option you have is removing the affected roots from your plant and tilling the soil around it. Always use sterile equipment.
If your nematode problem is very serious, you may also consider soil fumigation. This is when special pesticides applied to the soil release a gas that eliminates harmful microbes. Always read instructions carefully on these products.
Why Does My Mint Have Bugs?
Every pest has certain conditions that it thrives in. And if a particular infestation is troubling you, or keeps coming back, it’s best to diagnose what’s attracting them and most importantly, make the changes to keep them away.
Humidity can be a major influence on if a pest can thrive or not. High humidity can create ideal breeding grounds for pests to lay eggs in, including certain types of caterpillars like loopers and hairy caterpillars who do the most damage during the larvae phase.
More often than not though, it’ll be low humidity that causes the most pest problems for your mint plants. Mealybugs, spider mites, aphids, and more all prefer dry conditions from which to live in. Increasing humidity, either by watering more frequently, or misting your mint plant, can help alleviate this problem.
There’s a reason why most insecticides use dehydration to kill pests instantly – insects hate when they don’t have moisture.
For that reason, if your plant is too wet, or the soil is too soggy, you’re going to attract more attention from thirsty insects.
Additionally, damp conditions are a breeding ground for fungi and diseases too, which weaken your plant. And a weak plant is an easy meal for any pest.
If your plant has a moist appearance but its leaves are drooping, you may be overwatering your plant and creating too wet an environment.
Plants need a healthy airflow to thrive, and proper ventilation ensures your mint plant and the soil dries in good time. However, with poor ventilation, your plant and soil will become soggy, which pest infestations to full take advantage of.
Damp conditions are an ideal environment for the larvae form of any insect, including hairy caterpillars and loopers.
How to Get Rid of Mint Bugs Naturally
No doubt you’re growing your mint with the end goal of creating sweet fragrances and flavors in your cooking. For these reasons alone, you may wish to use natural pest controls in place of harsh chemicals.
I have a few suggestions for you to consider, all of which are effective ways of reducing and eliminating insects off your mint plant.
Oil sprays are a very effective natural remedy for pests and often contain fungicidal properties too, providing a huge defense boost for your mint plant.
Oil sprays work by suffocating soft-bodied insects such as mites and mealybugs, without impacting the plant’s growth at all, or harming useful pollinators like honeybees and butterflies.
Soap spray is one of the easiest-made, and most effective pest controls you can use on your mint plant! It will deal with everything from mealybugs, aphids, caterpillars, and more. The only thing to consider is that soap spray will only kill insects on contact, and not repel them.
Neem oil is a type of vegetable oil harvested from the neem tree, which deals with immature, larvae-state insects particularly well.
What I love most about using neem oil is that it’s super-effective against most of the common pests that afflict mint, including mealybugs, aphids, thrips, and mites.
The pungent smell of garlic is a great natural deterrent for many mint pests including beetles and spider mites. Think of a garlic spray as a preventative measure, as it will repel bugs before they set up on your plant and lay eggs.
Herbal Water Spray
Herbal sprays are versatile pest control. Depending on their ingredients, they can deter several pests at the same time. Many are fragrant, which acts as an insect repellent, whilst others contain naturally occurring oils such as neem that can kill insects on contact.
Chile pepper spray
Hot, spicey things are a major repellent to insects and will ensure your mint is foul-tasting and not worth the effort. Pepper sprays are especially effective if you’re having a hard time with aphids, loopers, and other soft-bodied insects.
If you want to attract more beneficial insects such as pollinating honeybees, whilst still repelling troublesome pests, then I highly recommend considering essential oils. Many essential oil sprays contain pungent fragrances, such as lavender, rosemary, peppermint, and more, which irritate most unwanted insects.
Pyrethrin is potent natural pest control that targets the nervous system of insects on contact. It’s particularly useful against moths and flies.
One thing I must stress to you about using pyrethrin is that it is highly toxic to pollinators such as honeybees and bumblebees.
If you want to rid your mint plant of ground-based pests such as beetles, mites, slugs, and more, diatomaceous earth should be your weapon of choice. When insects walk over this powder, they inhale it and die. Simply sprinkle it around your mint plant to create a barrier and repellent.
Sticky Trap/ Flying Trap
Stop pests right in their tracks with sticky traps. These are often glue-based and work by both repelling insects, or catching them if they wander too close. Place these around your mint plant to form a protective, preventative barrier.
Flying traps are often hung above and around your plant, and are especially effective against flying pests such as moths and aphids.
Tips to Prevent Bugs on Mint
- Inspect your plant regularly, checking for any foliage damage, cuts to the stem, or foul odors from the soil.
- Manually remove larger pests from your mint, including any laid eggs.
- Soapy water is an effective pesticide you can easily make at home. Always remember to dry off your mint plant after a few hours.
- Create physical barriers to prevent insects from crawling towards your plant. Sticky traps or diatomaceous earth can be placed around the perimeter of your mint.
- Ensure you are watering your mint plant appropriately. Too much or too little can cause the right conditions for an infestation.
- If treating an infestation, time your pest control right. For example, cutworms are most active at night, and so easier to spot.
- Improve air circulation for plants, especially if indoors or in greenhouses.
- Use other fragrant plants to act as a deterrent, such as lavender or peppermint.
- Healthier plants can fend off pests easier – ensure they are well-fed, growing strong, and have enough minerals/water to sprout new growth.
- If repotting plants, ensure the new pot and soil mixture is clean and free from any pests.
- If your mint plant is growing outside, you may wish to promote natural predators to pests, such as ladybirds, to your garden.
- Be patient – progress might be slow, but so long as the infestation is reducing in size gradually, keep at it!