Description of Butomus umbellatus (Flowering Rush)

Butomus umbellatus is flowering rush, a pond-edge favourite with pink starry flowers in summer. It’s easy to place and gives height without looking heavy.

Appearance

It forms clumps of narrow, reed-like leaves. Flower stems rise in summer and carry umbels of pink flowers. It typically reaches 60 to 120cm, depending on depth and feeding.

Care Guide

It prefers shallow water or saturated soil and plenty of light.

Sun: Full sun.
Soil: Aquatic compost or heavy wet soil.
Water: Shallow margins or saturated mud.
Division: Divide in spring if clumps get congested.
Tidy: Cut old stems down in late winter.

In baskets, top with gravel to keep the compost in place.

Suitability for Bog Garden

This suits bog gardens with a wet hollow, pond shelves, and the wetter edge of liner bogs. Place it mid-bed so the flowers sit above lower marginals.

Keep it out of deep water.

FAQ

When does it flower?
Usually in summer.

Can it grow in a bog garden?
Yes, in saturated soil or a shallow-water zone.

How tall does it grow?
Often 60 to 120cm.

Does it spread?
It forms clumps that expand slowly over time.