American Sweet Flag
Perennial wetland plant growing in dense stands, reaching 60-90 cm tall. Features sword-like leaves and a flower spike resembling foliage. Prefers consistently wet or saturated soils and full sun to partial shade. Often found along pond edges, streams, and in marshes. Has historical medicinal and culinary uses. Valuable for wetland restoration, rain gardens, and water feature margins. Provides cover for small wildlife and helps stabilize shorelines. Spreads via rhizomes, forming colonies in suitable conditions.
Plant Details
Bloom Colour: Green to Brown
Bloom Time: Early to Mid-Summer
Sun Requirements: Sun to Part-Shade
Moisture: Moist to Wet
Phenology: New shoots emerge from rhizomes in mid-May. Leaves reach full size by late June. Flower spadix develops June-July. Seeds mature late August. Foliage begins yellowing in October but often persists into winter, eventually laying flat. Dead foliage provides winter cover.
Wildlife Value: Rhizomes and seeds eaten by waterfowl and muskrats; provides cover for aquatic wildlife and wetland birds; moderate browse value for deer
Habit Over Time: Creates expanding colonies through thick, branching rhizomes that grow at or near the soil surface. While it spreads steadily, the sword-like foliage emerges in neat fans that allow other vigorous wetland plants to grow between them. Forms dense stands in optimal conditions but is easily contained through rhizome division.
Height: Medium (2-3 feet)