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Water Willow

Justicia americana

Last reviewed: October 2026

Justicia americana, or water willow, is an aquatic forb that grows in shallow streams and pond margins across much of the eastern and central United States, blooming from spring through fall with white orchid-like flowers that attract butterflies.

Water Willow (Justicia americana)
Photo: no rights reserved, uploaded by Evan Barker

Toxicity unknown

Water Willow (Justicia americana) is not listed by the ASPCA Animal Poison Control Center (opens in new tab) or the other sources we check, so we have no verdict for it either way. Absence from those lists is not a clearance. If your pet shows symptoms after eating any plant, call the ASPCA at (888) 426-4435.

The USDA PLANTS Database (opens in new tab) does not flag Water Willow as toxic to livestock.

Light

full sun

Water

medium

Size

12"–36" H × 12"–36" W

Bloom

Apr, May, Jun, Jul, Aug, Sep, Oct

Native to

AL, AR, DE, FL and 25 more states

Pollinators

butterflies

Before you buy

Your city may pay you to plant this

Cities and water utilities offer rebates for replacing lawn with native and water-wise plants. We track 460 programs across 44 states, each with a link to the provider and the date we last checked it.

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Picture natives in your own yard

Upload a photo of your yard and Patch Vision shows a rendering of it planted with natives for your region, like Water Willow.

Water Willow is a native perennial that thrives in moist soils and produces small white or pale purple flowers from spring through fall. This compact plant forms neat clumps and works well in areas with consistent moisture or near water features.

Growing Water Willow

Grow Water Willow in full sun and medium water. Mature plants reach 12 to 36 inches tall and spread 12 to 36 inches wide. Expect low maintenance to keep it looking intentional in a front yard.

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In an HOA neighborhood

Water Willow is an HOA-friendly choice. Maintenance level: low. Tidiness: 2 out of 5.

Works well in: front yard, foundation, street edge, mid zone.

Wildlife value

The long blooming season provides nectar for butterflies and other pollinators throughout most of the growing season. The dense growth habit also offers shelter for small wildlife.

Common questions

When does water willow bloom?
Water willow produces its white, orchid-shaped flowers from March into November, with peak bloom typically in the warmer summer months.
What growing conditions does Justicia americana need?
It grows best in full sun to part sun, rooted in shallow water or saturated mud along streambanks, riverbeds, and pond edges.
Do pollinators use water willow flowers?
Butterflies regularly visit water willow flowers for nectar during its long summer bloom period.
Is water willow a good plant for stream restoration?
Yes, its spreading rhizomes and dense stands help stabilize soft banks and slow erosion along slow moving streams and pond margins.
Is Water Willow toxic to livestock?
The USDA PLANTS Database does not flag Water Willow as toxic to livestock.
Is Water Willow HOA-friendly?
Water Willow is generally an HOA-friendly choice in the right placement, with low maintenance.

These answers were drafted with an AI model from this plant's data. Verify care details with a local expert.

Native range data from the World Checklist of Vascular Plants (Kew). Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.

If something looks wrong

Common plant problems, and what to check first

These come up on almost any plant. Each guide lists the likely causes in the order they are worth ruling out, with one thing to check before you act on any of them, and links to the source it came from.

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Ready to grow Water Willow? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.