Japanese sweet flag

Acorus gramineus | Also known as: Japanese rush | Rating: 0 votes | Print / Pdf

Japanese sweet flag can be used in bog gardens. I'm not sure how many people think “Ooh I'd love a bog garden, over there by the patio” but there you go. If you're a bog gardener, here's the perfect plant for you.

Acorus gramineus, or Japanese Rush is native to Japan and East Asia and loves a wet environment. It has shiny, curved and narrow leaves that are a greeny yellow colour and fragrant, growing to around a foot in length. It does have small yellow flowers, but they only bloom when the plant is in plenty of water. It's also suitable for growing in an aquarium as long as the aquarium has an open top so it can grow up and out of the water. It will grow in sun or light shade, a low maintenance plant.

Rate it:
Known dangers?
  • no
Height [m]
  • 0.08 - 0.35
Spread [m]
  • 0.1 - 0.15
Dominant flower colour
  • Inconspicuous or absent
Flower Fragrance
  • No, neutral please
Flowering seasons
  • Mid summer
Foliage in spring
  • Green
Foliage in summer
  • Green
Foliage in Autumn
  • Green
Foliage in winter
  • Green
Propagation methods
  • division
Growth habit
  • Clump-forming
  • Acidic
  • Neutral
  • Alkaline
Hardiness zone
  • Z10-11
Heat zone
  • H12-2
Winter temperatures [°C]
  • -1 - 4
Heat days
  • 1 - 210
  • well-drained but frequently watered
  • poorly-drained
  • boggy
Soil type
  • Clay
  • chalky
  • loams
Sun requirements
  • Full sun
  • Sheltered
Standard category
  • Aquatic & semiaquatic plants
  • Semiaquatic plants
Grown for
  • Ornamental Foliage
Creative category
  • For Beginners
  • Pond plants
Garden type
  • Bog garden
  • Cottage garden
  • Pond
Gardening expertise
  • beginner
Time to reach full size
  • 2 to 5 years
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