Plants against ants: 8 natural solutions for the garden

There is, however, a remarkably simple and environmentally friendly solution.

Ants perform an important job in the soil: they loosen it and clear away organic matter. Even so, they can become a nuisance in the garden, on the patio or even indoors. Before turning to poison baits or sprays, it is worth considering the power of particular plants. Certain species produce scents and active compounds that ants strongly dislike – and these can be used to good effect.

Why ants are troublesome in the garden – and when they are helpful

Viewing ants solely as pests is too simplistic. These insects aerate the soil, carry seeds and provide food for birds and other animals. They become a problem when they:

• build large nests beneath patio slabs or paths
• “farm” aphids in flowerbeds, weakening plants in the process
• enter the kitchen or food cupboards
• repeatedly disturb children playing on the lawn

If the aim is simply to manage them in specific areas, rather than reaching for heavy-handed measures, scent barriers are the answer. This is where certain herbs and perennials come into their own.

“Some garden plants emit signals that are so unpleasant to ants that they reroute their paths or abandon the nest.”

Plant-based deterrents: which species really drive ants away

Peppermint: a scented wall in a pot

Peppermint releases a powerful fragrance that disrupts ants’ scent trails. The insects navigate via these chemical pathways, so once they are masked, they can no longer find their route.

• Position: partial shade to full sun, in nutrient-rich soil
• Benefit: creates a scented barrier and provides leaves for tea and cooking
• Tip: always grow it in a pot, otherwise it will spread throughout the entire bed

A line of peppermint pots beside patio doors or wall cracks through which ants enter the house is particularly effective.

Lavender: attractive to look at, tough on ants

Lavender brings together garden beauty and a useful function. Its intense, resinous scent repels ants, although bees and bumblebees love it.

Plant lavender:

• alongside garden paths with frequent ant trails
• around seating areas and patios
• in sunny, relatively dry positions

This plant prefers lean, free-draining soil. Waterlogging quickly causes rot. Pruning after flowering keeps it compact and encourages further blooms.

Thyme: ground cover with an added benefit

Thyme has a pronounced fragrance that is aromatic and slightly medicinal. Ants generally avoid dense thyme mats, while the herb is also valuable in the kitchen.

“Thyme forms low carpets that fill gaps, path edges and sunny banks – and significantly slow ants down in those spots.”

Creeping varieties that grow over gaps between paving stones are especially suitable. A sunny site and free-draining, fairly dry soil are essential.

Rosemary: a fragrant hedge against marching ants

Rosemary is hardy, evergreen and rich in essential oils. While its spicy scent is pleasant to people, ants are more likely to interpret it as a warning.

• as a small shrub beside front doors and patios
• in containers along balcony railings
• in Mediterranean-style beds with gravel and sand

Rosemary copes extremely well with drought and heat. In colder regions, it needs winter protection or should be grown in a container that can overwinter frost-free.

Tansy: yellow flowers with real impact

Tansy is a robust perennial with vivid yellow flower clusters and strong insect-repelling properties. Many pest insects, including ants, avoid it.

It is well suited to:

• the edges of beds where aphids frequently occur
• wild, natural-style corners of the garden
• areas along fences or walls

The plant grows fairly tall and spreads widely. In small gardens, use it selectively and avoid placing it too close to seating areas, as its scent can be intense.

Basil: a kitchen favourite with a second job

Basil is indispensable in tomato salad, while also serving as a useful helper against ants. Its essential oils encourage the insects to avoid windowsills and balcony planters.

Benefit	Explanation
Quick effect	Fresh leaves release fragrance compounds immediately, particularly in sunlight.
Flexible use	Pots can be moved according to the ants’ route.
Double benefit	Protection from ants and a constant supply for the kitchen.

Important: basil needs plenty of water and warmth. The plant dislikes cold draughts and stagnant moisture.

Garlic: pungent scent, clear message

Garlic works on two levels. First, its strong smell deters ants; secondly, it helps reduce fungal diseases on neighbouring plants.

“Anyone who plants garlic cloves around beds or along walls creates an invisible scented line that ants generally will not cross.”

Garlic is particularly suitable for vegetable beds and for planting near roses or strawberries. Put the cloves in the ground in autumn or early spring.

Yarrow: delicate appearance, clear effect

With its fine leaves and delicate flower clusters, yarrow has a rather romantic appearance, yet it has a clear effect on a range of insect species. Ants are among them.

At the same time, it attracts beneficial insects such as parasitic wasps and ladybirds, which in turn consume aphids. Anyone dealing with ants around aphid-infested plants therefore benefits twice over.

How to use ant-repelling plants correctly

The right location makes the difference

For this approach to work properly, it is not enough to plant a few herbs anywhere at random. Key locations include:

• front doors and patio doors
• ground-floor windowsills
• cracks in paving where ants emerge
• the immediate area around ant trails in flowerbeds

A dense ring of plants has a stronger effect than individual pots placed far apart.

Combining several species

Mixing different herbs and perennials strengthens the result. One example of an anti-ant strip beside the patio is:

• rosemary and lavender at the back
• thyme in front as a low carpet
• peppermint and basil in pots between them

This creates an uninterrupted layer of scent that ants find difficult to cross.

Do not overlook maintenance

Many of these plants owe their effect to essential oils. The healthier and more vigorous they are, the stronger their fragrance. Regular pruning, suitable watering and sufficient sunshine are therefore crucial.

Extra tip: oils for rapid help with a severe infestation

If there is already a major ant trail in the house, essential oils from the plants mentioned can be used. Mix a few drops of peppermint, lavender or thyme oil with water, then wipe or spray it along the insects’ routes.

Important: use sparingly, and first test an inconspicuous area to check whether the surface tolerates the oil. Children and pets should not come into direct contact with the undiluted liquid.

Natural rather than chemical: what else helps

Plants against ants work best when a few basic rules are followed: keep food securely sealed indoors, do not leave sweet foods uncovered outside, and seal cracks and gaps wherever possible. The fewer incentives ants find, the more likely they are to retreat.

Choosing diversity in the garden brings a double benefit. Many of the species listed support bees, butterflies and other beneficial insects. This creates a stable balance in which ants are present but do not become a nuisance.

A brief reality check is also needed: no garden will be completely free of ants – nor would that be desirable. The aim is to keep them away from the patio, play area and house. Peppermint, lavender, thyme, rosemary, tansy, basil, garlic and yarrow achieve precisely this balance remarkably well.