
Sulphur yellow flowers, often with brown markings, appear from midsummer amongst the upright grey-green leaves of this vigorous water marginal. This native, evergreen yellow flag iris was once commonly found on marshy land and riversides and is ideal for planting at the margins of a large lake or pool. Iris pseudacorus also flourishes in deep, reliably moist soil that has been enriched with well-rotted organic matter. Great for wildlife and bog gardens, too.
How to care for Iris pseudacorus:
To encourage healthy growth of roots, foliage and flowers, feed with a general-purpose or slow-release aquatic fertiliser. Remove yellow or brown leaves to keep the plant healthy and the water clean. Cut water iris to just above the water line in autumn if you live in a cooler part of the country.
Flowering period:
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
Eventual height:
1.5m
Eventual spread:
1.5m
Position:
Full sun / light shade
Rate of growth:
Fast-growing
Soil:
Moderately fertile, moist, well-drained soil / Reliably damp or boggy
Hardiness:
Fully hardy
-
This perennial dies back to below ground level each year in autumn, then fresh new growth appears again in spring.
-
Humans/Pets: Harmful if eaten
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Sulphur yellow flowers, often with brown markings, appear from midsummer amongst the upright grey-green leaves of this vigorous water marginal. This native, evergreen yellow flag iris was once commonly found on marshy land and riversides and is ideal for planting at the margins of a large lake or pool. Iris pseudacorus also flourishes in deep, reliably moist soil that has been enriched with well-rotted organic matter. Great for wildlife and bog gardens, too.
How to care for Iris pseudacorus:
To encourage healthy growth of roots, foliage and flowers, feed with a general-purpose or slow-release aquatic fertiliser. Remove yellow or brown leaves to keep the plant healthy and the water clean. Cut water iris to just above the water line in autumn if you live in a cooler part of the country.
Flowering period:
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
Eventual height:
1.5m
Eventual spread:
1.5m
Position:
Full sun / light shade
Rate of growth:
Fast-growing
Soil:
Moderately fertile, moist, well-drained soil / Reliably damp or boggy
Hardiness:
Fully hardy
-
This perennial dies back to below ground level each year in autumn, then fresh new growth appears again in spring.
-
Humans/Pets: Harmful if eaten