What’s Eating My Mint? (Holes in Mint Leaves)

Mint is a lovely perennial herb that grows easily in most garden spaces. But if you’ve noticed holes in your mint leaves, you might be wondering what’s eating them. There are a number of pests that mint can attract and cause holes in the leaves. The good news is these pests can be identified and effectively treated in an organic and environmentally friendly way. Read on to learn what’s eating your mint leaves, how to remedy it and avert a future attack. 

Holes in Mint Leaves - What's Eating My Mint
Holes in Mint Leaves

What Causes Holes in Mint Leaves?

The most common cause of holes in mint leaves is pest attack. Flea beetles, mealybugs, aphids, caterpillars, and loppers are all pests that feed on the foliage of mint leaving holes in the leaves.

Let’s find out how to identify each pest and treat them naturally to salvage the mint leaves.  

Mint Pests Cause Holes in Leaves

Natural pests appear in many forms. If something has been feasting on the leaves of your mint, we can narrow the possibilities down to a few culprits. 

Flea Beetles Cause Holes in Mint Leaves

Flea Beetle - What's Eating My Mint Leaves
Flea Beetle

Flea beetles are soft-bodied insects that can really do a number on the foliage of your mint plant. If you come across small pin-sized holes dispersed throughout the mint leaves, take a closer look. These pesky bugs are small and dark in color and will usually be found in late summer hopping around your mint’s vegetation. By feeding on the leaves, flea beetles can severely compromise the overall health of the plant.

Mealybugs Cause Holes in Mint Leaves

Mealybugs - What's Eating My Mint Leaves
Infestation of Mealybugs

Mealybugs are a prevalent pest often found invading mint plants. The small oval-shaped insects can be identified by their unique white and fluffy wax covering. Warm and dry weather is their preferred climate.

Mealybugs insert their mouthparts into stems and leaves and extract sap, draining nutrients and the lifeforce of the mint plant. They produce honeydew, a sticky and sweet liquid. Honeydew often fosters the growth of mold and can attract even more pests. A mealybug infestation can quickly get out of hand and overtake a susceptible mint plant. 

Aphids Cause Holes in Mint Leaves

Aphids - What's Eating My Mint Leaves
Aphids

Any well-seasoned gardener has no doubt had run-ins with aphids. A bane of the garden, these pests are tiny but find their strength in numbers. Small, oval-shaped, and soft-bodied, aphids may not be detected right away. They also come in a range of colors including grey, black and green, which can help them blend into any plant.

They will usually attack fresh new mint growth and settle themselves on the undersides of the mint leaves.

Aphids subsist off of the nutritious liquids they suck from the mint foliage and young mint stems. After a time, mint leaves will appear damaged and discolored and plants may be left deformed or dead if neglected for too long. 

Caterpillar and Loopers Cause Holes in Mint Leaves

Looper Inchworm Cankerworm on Mint Plant - What's Eating My Mint Leaves
Looper (inchworm, cankerworm) munching on Mint Leaves

Infamous for devouring and defoliating whole leaves at a time, caterpillars and loopers (also called inchworms and cankerworms) can be a major nuisance to mint leaves and plants. Caterpillars are typically fuzzy and larger, whereas loopers are smooth, green, and move by making a half loop with their body.

It is imperative to act right away if you notice bite marks or mutilated mint leaves. An infestation of either of these pests can easily devastate a mint plant in a matter of days. 

Solutions for Holes in Mint Leaves

What's Eating My Mint and Causing Holes in Leaves

The good news is that there are many practical and holistic ways to deal with your pest problem on mint leaves. Seeing as how mint leaves are harvested and consumed, any substance you use should be mild and non-toxic. Here’s a short list of tried and true methods to rid your mint of these pests. 

Neem Oil for Mint Leaves

Neem oil is my go-to, all-natural pesticide and I really like this horticultural neem oil here. It has a pungent, somewhat citrusy smell to it. The oil is derived from the seeds of the neem tree. When made into a foliar spray, it is extremely effective at stopping pests in their tracks.

The oil smothers and immobilizes pests like mealybugs, aphids, and flea beetles. It also works well on larvae and eggs by preventing them from maturing and hatching.

Spray all the mint leaves and affected areas. A preemptive misting from time to time may help deter pests from getting settled.

Like all foliar sprays, do not apply during the heat of the day. 

Insecticidal Soap for Mint Leaves

Insecticidal soap is another natural substance that can be made into an effective spray for your mint plant. It will efficiently kill susceptible soft-bodied pests like mealybugs, aphids, flea beetles, and caterpillars on contact.

It can be combined with neem oil to produce an extremely potent, yet organic pesticide spray.

Sticky Traps for Mint Pests

Placing sticky traps like these ones, around your mint plant will either deter pests or prevent them from ever reaching your precious mint. Traps may work well as bait, attracting hopping flea beetles away from the plant. Once they’re stuck, they have no hope for escape.

Physically Remove Pests from Mint Plants

Sometimes the best method is to simply inspect mint plants and remove pests by hand. Caterpillars and loopers are large and visible enough to be disposed of manually. Pluck them off and eliminate them. Or, if you have chickens, repurpose the plump pests as a protein snack for your birds, they’ll love them.

Mint affected by aphids can be knocked off with a blast of water or selectively pruned to thwart an invasion.  

Preventing Mint Leaf Pest Attack

An old saying from Benjamin Franklin states that “An ounce of prevention is worth a pound of cure.” And, when applied to gardening, no truer words have ever been uttered!

There are many measures you can take to avoid the invitation of pests on your mint. These methods usually involve maintaining an environment that promotes healthy plants and discourages habitats that are appealing to pests. Here’s a short list of good mint plant care practices:

  • Routinely check your mint plant. Inspect for vegetation damage and the establishment of eggs or larvae. 
  • Physically remove as many visible pests as possible from your mint plant. 
Looper Inchworm Cankerworm on Mint Plant - What's Eating My Mint
Pick off pests to avoid them eating all your mint
  • Water your mint properly. Overly wet conditions attract a host of problematic pests. Waterlogged mint plants provide a perfect habitat for larvae, especially of caterpillars and loopers. Mint plants that do not receive enough water will be stressed, leading to weakness and vulnerability to pest infestations. 
  • Interplant your mint with other varieties of herbs and vegetables. The odor of other herbs may be offensive to certain pests. The diversity of flora will disrupt the potential of a major outbreak. 
  • Ensure adequate air flow among your mint plants. Keep them appropriately spaced to allow ventilation and sunshine to penetrate. Prune as needed to keep from crowding. Remember, many of these pests are soft bodied and will not thrive when exposed to direct sun. 
  • And always bear in mind the mantra “Right plant, right place.” If provided ideal growing conditions any plant can thrive. While mint is quite durable, make sure it has well drained soil, under full sun or partial shade. Keep the plant inspected, pruned, watered and fertilized. A healthy, vigorous mint plant has a much stronger capability to ward off pests by itself. 

Final Word

Mint can be planted once and it will spread and cover more ground year after year. I like to use mint around the edge of garden beds. It smells amazing and can help deter critters like rabbits, rodents, and deer.

Mint does have a tendency to take over garden beds though, so if there are no physical barriers to stop mint spreading, consider planting mint in pots or containers. This also makes it much easier to monitor your mint for any unwanted visiting pest attack and to take action to your mint happy and healthy.

You might also like to check out our article How To Grow Mint: Complete Guide To Growing Mint At Home for more information on growing mint and different mint varieties.

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