Ants
Family Formicidae
Among the most common insects in any garden, ants are usually harmless or even helpful, but they turn into a pest when they farm sap-sucking insects for honeydew. By protecting and spreading aphids, scale, whiteflies, and mealybugs from their predators, ants make those pests, and the sooty mold that follows, far worse.
🔎 How to spot it
Ants are familiar small insects with elbowed antennae and a narrow, pinched waist, traveling in trails. The pest connection is the giveaway: look for ants streaming up plant stems and trunks to tend colonies of aphids, soft scale, whiteflies, or mealybugs, often with sticky honeydew and black sooty mold nearby. Some ants also nest in beds and pots, loosening soil around roots, and a few bite or sting.
🥀 Damage it causes
Ants rarely damage plants directly. The harm is indirect: by guarding honeydew-producing insects from the lady beetles, lacewings, and wasps that would eat them, ants let aphid, scale, and whitefly populations explode, worsening that feeding damage and the sooty mold it causes. Nesting ants can also disturb roots and seedlings and farm pests onto new plants.
🛡️ Prevent it
Manage the honeydew makers, since ants follow the aphids and scale, not the plant itself. Encourage natural enemies and keep those sap-suckers in check so ants have less to farm. Keep mulch and debris from piling against stems where ants nest, and remove other attractions like spilled pet food and sugary trash near the garden.
🧯 If it is already here
Wrap a sticky band around tree trunks and woody stems to stop ants from climbing to the colonies they tend, which lets predators knock the aphids and scale back down. Use ant baits along trails to control the nest, the most effective chemical approach, rather than spraying foliage. Once the ants are gone, beneficial insects usually clean up the honeydew producers on their own.
💡 Good to know
Ants are best thought of as a symptom and an accomplice rather than the main pest: a trail of ants up a plant almost always means aphids, scale, or whiteflies are feeding above. Because the ants protect those pests from their predators, getting the ants off the plant is often the key that lets nature control the real culprits.
🌱 Plants it attacks
714 plants in the library can be attacked by this pest
Agapanthus
Ageratum
Anemone
Angelonia
Annual VincaFor educational and informational purposes only. Pest control advice is general guidance drawn from university cooperative extension sources; always identify a pest positively and read and follow the label on any product before use, especially around food crops, children, and pets.