Description of Mentha pulegium (Pennyroyal)

Mentha pulegium is pennyroyal, a low mint that likes damp soil and pond edges. It’s often used as a scented ground cover in wet spots, and it can flower well in summer if it gets sun.

Appearance

It forms creeping stems with small rounded leaves and produces lilac flower whorls along the stems. It usually stays 10 to 30cm tall but can spread into a wider patch in moist ground.

Care Guide

It likes steady moisture. Like many mints, it can run, so treat it as a plant you control rather than one you leave unattended.

• Sun: Full sun to part shade.
• Soil: Moist to wet soil with organic matter.
• Water: Keep consistently damp, especially in summer.
• Control: Grow in a pot sunk into the bog if you want to contain it.
• Trim: Trim after flowering to keep it compact and to encourage fresh growth.

If you want more plants, lift and replant small rooted pieces in spring. They usually take quickly in damp soil.

Suitability for Bog Garden

This is useful on the upper edge of bog gardens and around pond margins where you want low cover and scent. It also works between stones and at the front of raised bog planters.

In tiny bog gardens it can be too eager, so a container is the simplest way to keep it tidy.

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