Formicidae is a reference to the formic acid that they produce, and the word “ant” is derived from Middle English and means “the biter off”, obviously referring to their large jaws. I think everyone is familiar with the ant. They belong to the same order as wasps and bees and look very similar although most of them do not have wings. Winged ants are produced to go off and start new colonies. Typically of this order they have the very narrow connection between the thorax and abdomen. They have a similar social structure to bees that make hives and wasps that build communal nests.

Adult size: 0.75-50mm

Out and about

Aphids and scale feed in the warmer months so the ants will be out to get the honey dew secreted by them. Ants are found all over the world with the exception of Antarctica, in a diverse range of habitats and live in colonies. Most of the species of ants found in Australia do not occur anywhere else.

Reproduction and Life cycle

Ants live in colonies and have a queen, much like bees. The queen can control the sex and therefore what role these ants will have within the colony. Fertilized eggs can become female workers that nurse future eggs and larvae or females that are capable of becoming future queens themselves if there is a need to expand the colony. Unfertilized eggs develop into males whose sole purpose is to mate with a new queen. The queen creates her massive force of workers by being able to inhibit wing growth and reproductive organs in the female larvae. It is these worker ants that keep the colonies in order and that we see on plants

To deter

*Talcum powder - sprinkle around plants or over the nest if you can find it. *Borax - make a mix of 6 parts of sugar to1 part of borax, using a little water to first dissolve the borax. Honey can be added to make it into a paste. Place on something that can be covered so pets and children can’t get to it. The ants will be attracted to the sugar/honey and take it back to their nest where the borax will kill them. It damages their digestive systems and skeletons. *Coffee grounds - sprinkle around to repel ants *Cucumber and citrus peel - chop them up together and scatter around the base of the plants These are toxic to fungi that ants feed on so ants instinctively avoid them. *Bone meal - sprinkle around to repel ants. They hate the smell. *Spices – cinnamon, powdered curry or chilli sprinkled around plants in an unbroken line. *Diatomaceous earth- apply around the stem of the plant. DE pierces their exoskeletons causing dehydration and will also lodge in their leg joints, disabling and eventually killing them. *Place sawn-off milk cartons around the plants as a physical barrier NB talcum powder, borax mix and diatomaceous earth will all wash away with the rain.

To control

Plants to repel

Plectranthus (tropical coleus)- repels ants and insects / Tansy / Pennyroyal / Daisy family (including southernwood, mugwort, sagebush, wormwood and tarragon) / Chrysanthemums / Catnip / Lad’s love / Mint with parsley and spearmint

Plants to attract


Why they are both Beneficial & Pest
Ants have an important role in the environment. They are scavengers and collect debris which is then recycled back into the soil. Some plants attract ants specifically so they will protect the plant from insects which may harm it. Ants can also disperse seeds. As part of their scavenging, ants may gather small pests such as caterpillars and other larvae for food to take back to their nests. In the instance of protecting scale and aphids, however, they are very much a pest. Ants love the honey dew which aphids and scale secrete. They are fierce protectors of these insects and will fight off predators allowing the bugs to feed on the plants and continue to produce the honeydew. Ants actually ‘farm’ the aphids and will carry them from plant to plant which can spread viral diseases. Some ants will take aphid eggs back to their nests for the winter and in spring when new aphids have hatched; they will carry them to plants and continue farming the new generation. If ants are swarming over your plants there will probably be aphids or scale on the plant. A by-product from ants protecting the aphids and scale is sooty mould. This a is a black mould that grows on the honeydew which has dripped onto the leaves and stems of plants. Whilst the mould won’t directly harm the plant, it will interfere with the plants ability to photosynthesise.