Acorus gramineus

RHS Plant Profile
slender sweet flag
Herbaceous Perennial Grass Like Aquatic

A compact, semi-evergreen marginal aquatic perennial, comprising fans of leaves making clumps to a height of 30cm, with narrow mid-green leaves

Position

Full sun

Soil Types

Chalk, Clay, Loam

Max Height

0.1-0.5 metres

Max Spread

0.1-0.5 metres

Size

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

Growing Conditions

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

Position

Full sun
Aspect
South–facing or West–facing
Exposure
Exposed or Sheltered
Hardiness
H6

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Acoraceae
Native to GB/Ireland
No
Foliage
Semi evergreen
Habit
Clump forming
Genus
Acorus are deciduous or semi-evergreen, moisture-loving rhizomatous perennials forming tufts of linear or sword-shaped leaves, with insignificant spike-like flowers borne near the tips of central leaf-like stems
Name Status
Correct
Plant Range
E Himalaya to Japan & Philippines

How to Grow

Cultivation

Easy to grow in wet or very moist fertile soils. Can be planted in baskets in shallow water up to 10cm deep. It also makes a useful aquarium plant but is short-lived where water temperatures exceed 22°C for long periods. Divide every few years to prevent congestion. See pond plants and bog gardens for further information

Propagation

Propagate by division, in spring

Suggested planting locations and garden types

  • Cottage and informal garden
  • Low Maintenance

Pruning

Tidy old or damaged foliage in early spring if necessary

Pests

Generally pest-free

Diseases

Generally disease-free