American Senna
Senna hebecarpa
Last reviewed: September 2026
Senna hebecarpa is a tall perennial forb with bright yellow flower clusters that bloom from July through September, drawing bees and butterflies to meadows, thickets and roadside edges in medium moisture soil.
Toxicity unknown
American Senna (Senna hebecarpa) 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 sun
Water
medium
Size
24"–60" H × 18"–36" W
Bloom
Jul, Aug, Sep
Native to
CT, DE, IL, IN and 16 more states
Pollinators
bees, butterflies
Before you buy
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American senna is a native perennial that produces bright yellow flowers from summer through early fall. This upright plant has compound leaves and develops seed pods after flowering, creating seasonal interest in the landscape.
Growing American Senna
Grow American Senna in part sun and medium water. Mature plants reach 24 to 60 inches tall and spread 18 to 36 inches wide. Expect moderate maintenance to keep it looking intentional in a front yard.
In an HOA neighborhood
American Senna is an HOA-friendly choice. Maintenance level: moderate. Tidiness: 3 out of 5.
Works well in: mid zone, foundation.
- Can look somewhat informal during winter dormancy
- Seed pods may be considered messy by some
Wildlife value
Host plant for cloudless sulphur butterfly, orange sulphur butterfly.
The bright yellow flowers attract various bees and butterflies during its long blooming period. Seeds provide food for birds and small wildlife.
Common questions
- How much light and water does Senna hebecarpa need?
- Senna hebecarpa grows best with part sun, tolerating conditions from full sun to part shade, and prefers evenly moist, medium moisture soil rather than very dry or constantly wet ground.
- When does Senna hebecarpa bloom?
- Senna hebecarpa flowers from July through September, producing upright clusters of yellow blossoms that stand out in late summer meadows and open woodland edges.
- What pollinators visit Senna hebecarpa?
- Bees and butterflies are the main visitors to Senna hebecarpa, working the yellow flowers for pollen through the summer bloom period.
- What growing conditions suit Senna hebecarpa best?
- This forb does well in part sun with medium moisture soil, and is often found along roadsides, meadow margins, and the edges of thickets where it gets a mix of light and shade.
- Is American Senna HOA-friendly?
- American Senna is generally an HOA-friendly choice in the right placement, with moderate 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 vouchered herbarium specimen records and regional native plant society lists. 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.
- It is dying right after planting
- Leaves turning yellow
- Wilting even though I watered it
- Brown crispy leaf tips
- Bugs on the plant
Ready to grow American Senna? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.
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