How Do I Keep Fire Ants Out of My Raised Beds?

“How do I keep fire ants OUT of my raised beds? I’m in Texas, and those buggers are devastating! I hate to poison my food … any advice would be appreciated.” Question from Amy of Terrell, Texas

Answer: The red fire ant (Solenopsis invicta) is an introduced species that’s a painful problem down South, and gardeners with fire ant problems really pay the price. Thankfully, there are organic ways to manage them.

About Fire Ants

Let’s start with an overview of these pests. Fire ants create large mounds that can reach a foot and a half in height. A big colony may contain up to 200,000 worker ants and queens can lay up to 800 eggs a day. These pests thrive in southern climates and start causing troubles as soon as the soil warms up in spring. They are small, brownish orange, and have painful, venom-injected stings that hurt like fire. They like to feed on young plants and seeds, so they are attracted to gardens.

Organic Fire Ant Control

If you know where they are nesting in your raised bed, start with this simple method as early in the season as possible, before you start planting. Pour boiling water over their nests, being sure to cover the full nest area deeply. This will immediately kill nests in your beds.

Once you have weeded and turned your beds for the season, spray any ants you see with OMRI Listed spinosad, a natural bacterium that is toxic to insects like ants and approved for organic gardening. You can also buy spinosad ant bait traps for your garden, which won’t harm other insects. Follow the manufacturer’s instructions.

Bait traps that container borax are another option.  Borax is a natural ingredient that is non-toxic to us. TERRO® Liquid Ant Baits work very well.

If more colonies appear, you can also cover them with diatomaceous earth (food grade). This has been proven to ward off ant colonies naturally. It also would not hurt to put rings of diatomaceous earth around your favorite plants.

Finally, another safe spray to use that’s effective in repelling fire ants is D-limonene (Orange Guard). It is OMRI Listed for organic gardening and is made from the extract of citrus peels. It really keeps ants away. Follow the manufacturer’s application guidelines.

I hope this helps with your ant problems!

Jessie Keith

Black Gold Horticulturist