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Lesser Marsh St. Johnswort

Triadenum tubulosum

Last reviewed: June 2026

Lesser Marsh St. Johnswort (Triadenum tubulosum)
Photo: (c) Laura Clark, some rights reserved (CC BY), uploaded by Laura Clark

Light

part sun

Water

high

Size

6"–24" H × 4"–12" W

Bloom

Jun, Jul, Aug, Sep

Native to

FL

Pollinators

bees, beetles

Browse plants for this ecoregion

Lesser marsh St. Johnswort is a compact native perennial that thrives in consistently moist soils and partial sun conditions. It produces small yellow flowers from summer through early fall and maintains a low, bushy growth habit. This wetland plant is ideal for rain gardens, pond edges, or areas with poor drainage.

In an HOA neighborhood

Lesser Marsh St. Johnswort takes more care to keep looking intentional in a front yard. Maintenance level: low. Consider it for backyard or mid-zone beds rather than the street edge.

Works well in: backyard only.

  • Requires consistently wet conditions that may look messy
  • Unknown winter appearance could be problematic
  • Small stature may appear unkempt in formal landscapes

Wildlife value

The flowers attract native bees and beetles during the long blooming season from June through September. Its presence in wet areas also supports beneficial insects that contribute to overall garden ecosystem health.

Common questions

How much sun does Lesser Marsh St. Johnswort need?
Lesser Marsh St. Johnswort grows best in part sun conditions.
When does Lesser Marsh St. Johnswort bloom?
Lesser Marsh St. Johnswort blooms in June, July, August, and September.
Where is Lesser Marsh St. Johnswort native?
Lesser Marsh St. Johnswort (Triadenum tubulosum) is native to FL, per the USDA PLANTS Database and regional native plant society lists.
What pollinators does Lesser Marsh St. Johnswort attract?
Lesser Marsh St. Johnswort draws bees and beetles.
Is Lesser Marsh St. Johnswort HOA-friendly?
Lesser Marsh St. Johnswort 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 USDA PLANTS Database and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.

Ready to grow Lesser Marsh St. Johnswort? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.

Not sure where to start? Take the 2-minute yard quiz