Nature on our doorsteps: Selfheal in the lawn

Rosaleen Dwyer is the County Heritage Officer at South Dublin County Council – every week she gives us an insight into nature on our doorsteps and the beautiful biodiversity of its plants and wildlife.

There are a number of low-growing wildflowers that regularly pop up in the lawn, particularly if the lawn is not cut too tightly or too often.

These include the humble Daisy, the golden Creeping Buttercup, and the honey-scented Red and White Clovers.

A less well-known plant that can also occur is Selfheal.

This plant is often only first noticed when it comes into flower, as it brings another colour into the lawn – patches of lilac blue or purple.

A close look at the plant shows that its individual flowers are in fact quite small, and that these flowers are arranged snugly around a cylindrical head or flowering spike.

Small, red-coloured bracts (false leaves) separate the flowers from one another.

These red bracts turn brown when the flowers are finished and have dropped their petals.

Although small in size, Selfheal’s flowers are rich in nectar, and they attract long-tongued pollinating insects including bumblebees and butterflies.

The plant has been used in traditional medicines around the world for centuries.

Today, scientific studies continue to test the plant for useful medicinal compounds.

Its flowers and stems have also been used to produce a dye, delivering a deep olive-green colour.

Selfheal generally grows in damp meadows and pastures, along hedgerows and roadside verges, and at the edges of woodlands.

In these habitats, its flowering stems can grow up to 30cm to 40cm tall.

When it grows in the lawn, however, Selfheal acts a little differently.

In response to the regular pattern of mowing, it keeps its head very low.

Instead of taking the time to let its flowering stems grow tall, the lawn Selfheal rapidly sends up a very short flowerhead.

By doing this, Selfheal is hoping that its flowers will be around long enough to be pollinated before the mower is back again.

Selfheal is tolerant of trampling, allowing it to survive and spread in lawns which are used a lot by us.