Virginia Marsh St. John's-wort
Triadenum virginicum
Found in bogs, fens, tidal swamps and marshes, other peaty wetlands. Weakley, Flora of the Southeastern United States (2025), Northern Tier edition What its natural habitat tells you
Native to West Virginia. How scores work Is it native here?
Profile 88%
- Height
- Up to about 28 inches
- Light
- Partial shade, Full shade, Full sun
- Soil moisture
- Moist to wet
No photograph yet. Looking for an old drawing…
At a glance
- Life cycle
- Perennial
- Bloom
- July to September
Not yet recorded · Spread · Leaves
Recorded in 4 West Virginia counties.
Natural habitats
Places it grows wild. Not a planting requirement. Each habitat page lists the plants and wildlife also found there.
Wet, open, peaty mountain wetlands fed by seepage, often with sphagnum moss.
Open, herb-covered wetlands with fresh, non-tidal water.
Forested wetlands with standing water much of the year, such as cypress and gum swamps.
Who uses this plant?
22CaterpillarsGenus host records with ranges including WV
Genus host records with ranges including WV · Hypericum
- Acleris maculidorsanaStained-Back Leafroller Moth
- Choristoneura rosaceanaOblique-Banded Leafroller Moth, Rosaceous Leaf Roller
- Dejongia lobidactylusLobed Plume Moth
- Eupithecia miserulataCommon Eupithacia, Common Pug
- Hyppa xylinoidesCommon Hyppa
- Iodopepla u-albumBurgundy St. Johnswort Moth, White-Eyed Borer
- Iridopsis ephyrariaPale-Winged Gray
- Melanchra assimilisBlack Arches
- Mocis latipesSmall Mocis, Striped Grass Looper
- Nedra ramosulaGray Half-Spot
Show all 22
- Nemoria bistriariaTwo-Striped Emerald, Red-Fringed Emerald
- Nemoria tuscaroraAppalachian Emerald
- Phlogophora irisOlive Angle Shades
- Platynota flavedanaBlack-Shaded Platynota
- Probole amicariaFriendly Probole
- Sparganothis sulfureanaSparganothis Fruitworm Moth, Sulfur Leafroller, False Yellow-Head
- Synchlora aerataWavy-Lined Emerald, Camouflaged Looper
- Xestia c-nigrumSpotted Cut-Worm, Setaceous Hebrew Character, Lesser Black-letter Dart
- Zale lunataLunate Zale
- Agonopterix lythrella
- Caloptilia hypericella
- Xenotemna pallorana
43BeesSoutheastern regional records
Southeastern regional records · Hypericum
Individual names are not available yet.
Noori, Seltmann & Orr 2026, A curated and integrated dataset for exploring global bee-plant interactions (GloBI), Zenodo, CC BY 4.0
1BirdsRecorded genus food-resource interactions; not a state feeding claim
Recorded genus food-resource interactions; not a state feeding claim · Triadenum
- Aix sponsaWood Duck
Direct food only: birds recorded eating this genus across North America. Caterpillars on host plants also feed nesting birds. NC Native Plant Society: butterfly gardening
No records yet · Ants · Beetles · Flies · Adult butterflies / moths · Other wasps · Other insects
Plant details
- Family
- Hypericaceae
- Flower color
- Pink
Safety has not been reviewed for this plant; check toxicity and thorns before planting.
Growing sources and scope
- Bloom · “July to September” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- Flower color · “Pink” · Lady Bird Johnson Wildflower Center
- Height · “Up to about 28 inches” · Lady Bird Johnson Wildflower Center
- Life cycle · “Perennial” · Lady Bird Johnson Wildflower Center
- Light · “Partial shade; Full shade; Full sun (documented habitat)” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- primary_flower_color · “pink” · Lady Bird Johnson Wildflower Center
- Soil · “Moist; Wet (documented habitat)” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
Also known as
Virginia Marsh St. John's wort; Virginia Marsh St. Johnswort; john's wort; john's-wort
Conservation status
| West Virginia rank | S4 |
|---|---|
| Global rank | G5 |
| WV status | Not verified |
| Federal status | Not verified |
Will it fit your yard?
Check this plant against your county, sun and soil moisture. Conditions are checked in your browser.
Sources
- NatureServe Explorer
- USDA PLANTS
- Vascular Plants of North Carolina (NC Natural Heritage Program)
- Weakley, Flora of the Southeastern United States (2025), Northern Tier edition
- West Virginia occurrence source
- Shropshire & Tallamy 2025, Lepidoptera of North America north of Mexico, ZooKeys 1261 (ODbL)
- Noori, Seltmann & Orr 2026, A curated and integrated dataset for exploring global bee-plant interactions (GloBI), Zenodo, CC BY 4.0
- Smith, Bachelder, Russell, Morales, Mosher & Seltmann 2024, Bee-Specialization-Modeling v0.6.1 (specialist host table compiled from J. Fowler's pollen specialist bee lists), Zenodo, CC BY 4.0
- Hurlbert, Olsen, Sawyer & Winner 2021, Avian Diet Database, Scientific Data 8: 260 (CC0)
- Narango, Tallamy & Shropshire 2020, Few keystone plant genera support the majority of Lepidoptera species, Nature Communications

