Mystery bugs on basil turn out to be armyworms that can strip a plant fast

Fresh basil is one of the quickest ways to make a home garden feel worth the effort. It tastes better than store-bought herbs and gives gardeners a fast, satisfying crop to harvest for months. But that payoff can disappear quickly when mystery pests show up and start chewing through leaves.

That was the issue in a Reddit post on r/gardening, where one gardener asked, “What are these bugs on my basil?” One of the images shared with the post features one small basil leaf on the plant turned up to reveal several little creepy crawlies.

Many beet armyworms on a basil leaf.

Photo Credit: Reddit

Commenters quickly suggested an ID for the pests as beet armyworms, a common pest on basil that can strip a small herb plant quickly if left unchecked.

They often hatch in groups and feed together on the same leaf, one user noted. They added that the black specks visible nearby, likely frass, or caterpillar droppings, were another sign that the pests were actively feeding on the plant.

For gardeners facing the same pest, the suggested fix is straightforward and inexpensive. As the same commenter advised, remove the infested leaves or tips, dispose of them in soapy water or a sealed bag, and then check the plant over the next several days for any stragglers.

The original poster later said the pests were gone by the time they returned to deal with them, but they still removed the affected leaves, rinsed the plant, and applied a natural insect repellent.

Other gardeners recommended using BT, or Bacillus thuringiensis, a naturally derived treatment that targets caterpillar pests.

Another also suggested building longer-term protection with companion planting, such as growing basil alongside tomatoes and marigolds, and encouraging beneficial insects instead of reaching for harsher pesticides.

Catching pests early means gardeners can keep harvesting fresh leaves instead of buying pricier clamshell herbs from the store.

From an environmental perspective, the advice in the thread focused on avoiding broad-spectrum pesticides that can harm pollinators and other beneficial insects.

Using manual removal, BT, and other targeted methods can help gardeners protect basil while reducing unnecessary chemical use in the yard.

The overall takeaway was reassuring: If tiny clustered caterpillars show up on basil, gardeners may be able to solve the problem with quick action, daily checks, and low-chemical pest control, and get back to growing one of the most useful and delicious plants in the garden.

“I’ll say. Those armyworms have a refined palate if they like basil,” one commenter joked.

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