The chemical treatments available to treat ants can’t be used indiscriminately with pets or other animals, nor are they suitable for general garden use. It’s important to read the instructions carefully and, as with any garden chemical, follow them to the letter. Ants rapidly built up resistance to chemicals. To reduce this, alternate between products with different active ingredients. This is the actual chemical and it’ll be listed somewhere on the product.
There’s one biological control available – Steinernema feltiae, a pathogenic nematode, for treating ants’ nests in lawns and flower borders. The microscopic, worm-like nematodes are watered into the soil in places where ants are bringing soil up onto the surface. This is best applied in spring or autumn, when the ground is relatively moist. Several suppliers offer mail order, including Agralan.
There are plenty of practical steps that you can take to deter ants. Sit pots on feet and smear a generous amount of petroleum jelly that’ll prevent ants crossing. These materials will need regular topping up, especially if the weather’s hot.
A better bet maybe to apply a double-sided sticky tape. Copydex offers a product for joining carpets that might work well, but check it after wet weather. It’ll probably need replacing as it becomes soiled with dust and debris. Proprietary grease bands, as used on fruit trees, could also be used.
If you’re laying a new patio don’t bed the slabs on dabs of cement, which is not a very good method in any case. Instead, lay a continuous bed of cement and set your slabs on it. This will prevent ants tunnelling between the slabs. Brick pavers laid on sand are best avoided totally.
Four more patio pests
The creamy-white grubs live in compost and eat away at the roots of plants, which then wilt and may die.
Slugs and snails
These pests manage to get everywhere, even hanging baskets! Use pellets or alternative methods of control.
Sap-sucking insects that attack a wide range of plants. A bad infestation will cause distortion and reduced vigour.
Red lily beetle
This is the number one pest of lilies and fritillaries. Squash the beetles as soon as you discover them.