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American Pillwort

Pilularia americana

Last reviewed: August 2026

American Pillwort (Pilularia americana)
Photo: (c) Paúl Gonzáles, some rights reserved (CC BY), uploaded by Paúl Gonzáles

Toxicity unknown

American Pillwort (Pilularia 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.

Light

part shade

Water

high

Size

1"–3" H × 2"–4" W

Bloom

N/A

Native to

AL, AR, CA, GA and 9 more states

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 459 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

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American pillwort is a tiny aquatic fern that forms small clumps of grass-like fronds in wet soils or shallow water. This diminutive native plant stays very low to the ground and requires consistently moist to wet conditions to thrive.

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In an HOA neighborhood

American Pillwort takes more care to keep looking intentional in a front yard. Maintenance level: high. Consider it for backyard or mid-zone beds rather than the street edge.

Works well in: backyard only.

  • Requires specialized wet conditions unsuitable for typical landscaping
  • Extremely small size makes it nearly invisible in standard plantings
  • May appear weedy or unkempt without proper water garden context

Wildlife value

This small fern provides limited direct wildlife value but contributes to wetland ecosystems. It may offer some habitat for small invertebrates in water garden settings.

Common questions

How much sun does American Pillwort need?
American Pillwort grows best in part shade conditions.
Where is American Pillwort native?
American Pillwort (Pilularia americana) is native to AL, AR, CA, GA and 9 more states, per the World Checklist of Vascular Plants (Kew).
Is American Pillwort HOA-friendly?
American Pillwort takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

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.

See all plant problem guides

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