The broad array of aquatic and semi-aquatic plants we can grow in the Willamette Valley, and locally here in Corvallis, Oregon, includes a number of native plants.
These plants are suited for tough streamside conditions, or wetland sites, but they can also be used in man-made ponds and bogs.
It is quite possible to develop an attractive water feature for the native landscape that uses only native flora. And even for the gardener that is not a native plant fanatic, these PNW native water plants offer great appeal and reliable growth.
Top 9 PNW Native Water Plants
Here are a few PNW native plants to add interest and local flair to a bog, stream, pond, or other water feature:
Adiantum aleuticum (Maidenhair Fern) – Grows in moist soil at pond edge, or in-stream. About 2 ft. tall. Prefers shade.
Allium validum (Swamp Onion) – Grows in moist soil, bog, in-stream or very shallow water. Pink flowers early summer, up to about 2 ft. tall. Likes sun.
Arnica amplexicaulis (Streambank arnica) – Grows in moist soil at pond edge. Yellow flowers in summer, to 2-3 ft. tall. Likes sun.
Darmera peltata (Indian Rhubarb) – Grows in bog, in-stream, or shallow water. Flowers before leaves emerge in spring, pink clusters up to 2-3 ft. tall; foliage is large and lush to about 4-5 ft. Good fall color. Likes sun or partial shade. Spreading by rhizomes, may need to thin or divide every few years.
Mimulus (Monkey Flower) – Grows in moist soil, bog, or in-stream. 18″ tall but spreads. Plants bloom in summer: yellow flowers for Mimulus gutatus, pink for Mimulus lewisii. Both are adaptable from full sun to substantial shade. May spread by both roots and seeds.
Sagittaria latifolia (Wapato, Broadleaf Arrowhead) – Grows in moist soil, bog, or shallow water. White flowers on spikes 2-3 ft. tall in summer. Arrowhead foliage up to 3-4 ft. tall. Prefers sun, will tolerate some shade. Spreads by tubers.
Saxifraga oregana (Oregon saxifrage) – Grows in moist soil, bog, or in-stream. White spring flowers on a stalk 1-3 ft. above cluster of leaves at base. Likes sun.
Sidalcea cusickii (Cusick’s Checkermallow) – Grows in moist soil at pond edge, or just barely in-stream. Dramatic pink flowers 3-4 ft. tall in late spring and early summer. Large and lush foliage mass, also up to 4 ft. tall. Prefers full sun.
Sisyrinchium (Blue-eyed/Yellow-eyed Grass) – Grows in moist soil, bog, in-stream, or very shallow water. Several varieties native into our region: Sisyrinchium idahoense has bluish-purple flowers about a foot tall from mid-spring to early summer; Sisyrinchium bellum has the same form and color – they aren’t easily told apart. Sisyrinchium californicum is similar, but flowers are bright yellow. All have slender iris-like leaves, and may be evergreen in our mildest years. All prefer full sun, but will tolerate a little shade.