Ron asks: Ants have invaded my compost. How can I get rid of them?
Ron asks: Ants have invaded my compost. How can I get rid of them?
Tropical Gardener Answer: Ants will occasionally invade compost piles or enter vermicompost bins or mechanical compost mixers. Their presence is not all bad as they can introduce bacteria and fungi that help with decomposition. They also move the compost around and help aerate it. If, however, it appears they have made your compost pile their home, you can take several steps to discourage them or get rid of them.
As many as 40 different species of ants live in Hawaii. With the exception of the little fire ant and a few other stinging species, most are not harmful. Different ant species have different feeding habits that can include sweets, greasy material or starches as well as plant and animal material. Since many of these things are in your compost, ants may find their way to your pile. If they are occasional visitors and not causing harm or setting up shop, you don’t need to do anything.
Preventing ants from inhabiting your compost and discouraging those that do arrive occasionally depends on some good maintenance practices. Inspect all the materials that you put into your compost to be sure they do not contain ants. Be sure you don’t inadvertently introduce ants to your pile.
If ants arrive on their own and start taking over, you might need to take action to discourage them or get rid of them completely. Ants are likely to set up shop in your compost if it is dry. Keeping the moisture level so that it resembles that of a wrung out sponge will definitely discourage ants from staying. If your pile is open, cover it with a tarp or plastic to hold in the moisture. Be sure to open it regularly to insure the proper air circulation and prevent anaerobic fermentation. Another way to keep ants from settling in is to turn your pile often. In mechanical compost mixers, maintaining the proper moisture level and turning it often should keep ants from staying in these devices, as well.
As compost breaks down, it produces heat. With proper moisture and frequent turning, the pile will heat up as the material decomposes. Ants definitely don’t like hot piles, which in ideal conditions can reach 140 degrees or higher at the center of the pile.
If you still have an ant problem after correcting your maintenance, you can install some outdoor ant stakes that contain bait that the ants will carry back to the nest and kill lots of ants. Keep in mind that these baits contain insecticides that may be toxic to birds and pets, so select carefully and place them to be inaccessible to other critters. Any other powders or any poisons are not recommended since they may kill beneficial organisms in your compost or cause problems wherever you spread the finished product.
Diana Duff is a plant adviser, educator and consultant living on an organic farm in Captain Cook. Email plant questions to konamg@ctahr.hawaii.edu for answers by Certified Master Gardeners. Some questions will be chosen for inclusion in this column.
Gardening Events
Saturday: “Work Day at Amy Greenwell Garden” from 9 a.m. to 12:30 p.m. Meet at the Garden Visitor Center across from the Manago Hotel in Captain Cook. Volunteers will be able to help with garden maintenance and are invited to bring a brown bag lunch. Water and snacks provided. Call Peter at 323-3318 for more information.
“Friends of Amy Greenwell Garden Day” starting at 2:30 p.m. with Garden Tours until 4 p.m. From 4 to 6 p.m. a Special Program and pupus. Come enjoy the day and learn about the future of the garden and how you can become a “Friend.” Open to all. $5 donation requested. For information, call Maile Melrose at 323-3378.
Farmer Direct Markets
Wednesday: “Hooulu Farmers Market” 9 a.m. to 2 p.m. at Sheraton Kona Resort &Spa at Keauhou Bay
Wednesday: “Sunset Farmers Market” 2 p.m. to sunset at the north makai corner of the Kmart parking lot.
Saturday: “Keauhou Farmers Market” 8 a.m. to noon at Keauhou Shopping Center
“Kamuela Farmer’s Market” from 7 a.m. to noon at Pukalani Stables
Sunday: “South Kona Green Market” 9 a.m. – 2 p.m. at Amy Greenwell Garden in Captain Cook
Tuesday–Saturday: “U-Pick greens and produce” 10a.m. to 4p.m. Tropical Edibles Nursery, Captain Cook.
Plant Advice Lines
Anytime: konamg@ctahr.hawaii.edu
Tuesdays and Thursdays: 9 a.m. to noon at UH-CES in Kainaliu – 322-4892
Mondays, Tuesdays and Fridays: 9 a.m. to noon at UH CES at Komohana in Hilo 981-5199 or himga@hawaii.edu