Utah Plant Pest Diagnostic Lab

Ant Colony

Question:

I have just discovered an ant colony in my outdoor herb pot. I noticed soil build up around a couple of the herbs, thyme and rosemary and also soil build up around the drain holes. This pot is 20 inches across and 15 inches deep. How can I get rid of the ants without damaging the herbs or poisoning my family? Thank you.

Answer:

I recommend that you re-pot your herbs in fresh potting mix. The ant nest is probably inside the potting mix inside the pot. Take the entire container to the outer edge of your yard, furthest away from your home. Dump the whole thing, perhaps loosening the potting mix before tipping the container over. Shake the root systems of your herbs and dip them in a tub or bucket of water to remove all the ants. Clean out the container with a sharp stream of water and perhaps a scrub brush.

Prune the herb roots and perhaps the plant tops to make re-planting easier. Move the re-planted container to a new site just in case the ants were traveling to and from a nest somewhere nearby.

Good gardening!

Posted on 3 May 2007
Maggie Wolf
Horticulture Agent, Salt Lake County