Poison-hemlock
Conium maculatum
In the Carolinas and Georgia, found in ditches, roadsides, streambanks, river terraces, pastures, disturbed areas. Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition What its natural habitat tells you
Not native to Louisiana. Not suggested for planting. How scores work Is it native here?
Profile 71%
- Height
- 6–10 feet
- Spread
- 4–5 feet
- Light
- Full sun, Partial shade
- Soil moisture
- Usually moist
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Do not plant. Listed invasive in Louisiana.
Highly poisonous. Serious poisoning risk if eaten. Excluded from default planting suggestions; keep away from children and pets. Plant caution source
Hidden from default planting suggestions. Wildlife value and native status remain unchanged.
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At a glance
- Life cycle
- Biennial or perennial
- Bloom
- May to July
- Fruiting season
- June to August
Not yet recorded · Leaves
Recorded in 3 Louisiana parishes.
Natural habitats
Places it grows wild. Not a planting requirement. Each habitat page lists the plants and wildlife also found there.
Roadsides, fields and disturbed ground
Ground opened by people: roadsides, old fields, pastures, fencerows and lots.
Streams, rivers and their banks
Flowing water and its banks, bars and rocky shoals.
Who uses this plant?
3CaterpillarsGenus host records with ranges including LA
Genus host records with ranges including LA · Conium
- Choristoneura fumiferanaSpruce Budworm Moth
- Papilio polyxenesBlack Swallowtail, Celery Caterpillar, Fennel Worm, Desert Black Swallowtail, Parsnip Swallowtail
- Platynota stultanaOmnivorous Leafroller
Plant details
- Family
- Apiaceae
- Flower color
- Pink or white
- Fruit begins
- June
- Fruit ends
- August
Growing sources and scope
- Bloom · “May to July” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- Flower color · “Pink or white” · NC Extension Plant Toolbox
- Fruit begins · “June” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- Fruit ends · “August” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- Height · “6–10 feet” · NC Extension Plant Toolbox (ranked first; Minnesota Wildflowers differs)
- Life cycle · “Biennial or perennial” · NC Extension Plant Toolbox (ranked first; Minnesota Wildflowers differs)
- Light · “Full sun (6 or more hours of direct sunlight a day); Partial shade (direct sunlight only part of the day, 2-6 hours)” · NC Extension Plant Toolbox
- Soil · “Moist” · NC Extension Plant Toolbox
- Spread · “4–5 feet” · NC Extension Plant Toolbox
Also known as
Poison Hemlock
Conservation status
| Louisiana rank | SNA |
|---|---|
| Global rank | G5 |
| LA status | Not verified |
| Federal status | Not verified |
Sources
- NatureServe Explorer
- USDA PLANTS
- Weakley, Flora of the Southeastern United States (2025)
- Louisiana 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


