Butomus umbellatus

RHS Plant Profile
flowering rush

Other common names

grassy rush, lily grass, water gladiolus, engraff

Plants for pollinators
Aquatic Bogs

A rush-like, marginal aquatic perennial to 1.5m tall, with upright, twisted grassy, mid-green leaves that turn bronze-purple then dark green as they extend, and stiff stems bearing umbels of fragrant rosy-pink flowers 2cm in width in late summer

Position

Full sun

Soil Types

Clay, Loam, Sand

Max Height

1-1.5 metres

Max Spread

0.1-0.5 metres

Size

Time to Maturity
2–5 years
Max Spread
0.1-0.5 metres
Max Height
1-1.5 metres

Growing Conditions

Clay Loam Sand
Moisture
Poorly–drained
pH
Acid or Alkaline or Neutral

Position

Full sun
Aspect
South–facing or West–facing
Exposure
Exposed or Sheltered
Hardiness
H5

Colour & Scent

Fragrance Flower
Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Butomaceae
Native to GB/Ireland
Yes
Foliage
Deciduous
Habit
Submerged, Tufted
Genus
Butomus are submerged rhizomatous perennials with narrowly strap-shaped leaves and 6-petalled pink flowers held in umbels well above water level
Name Status
Correct
Plant Range
Eurasia

How to Grow

Cultivation

Grow in fertile mud at pond margins or in water up to 25cm deep, in full sun. See pond plants and bog gardens for further advice

Propagation

Propagate by seed sown as soon as ripe or by rhizome division in spring

Suggested planting locations and garden types

  • Wildlife gardens
  • Cottage and informal garden

Pruning

Cut back after flowering

Pests

May be susceptible to water lily aphid

Diseases

Generally disease-free