Tidalmarsh Amaranth
Amaranthus cannabinus
Last reviewed: June 2026
Light
full sun
Water
high
Size
12"–48" H × 6"–24" W
Bloom
Jul, Aug, Sep
Native to
CT, DE, FL, GA and 11 more states
Tidalmarsh amaranth is a tall annual wildflower that thrives in wet conditions and full sun. It produces clusters of small greenish flowers from July through September and can reach up to 4 feet in height. This native plant requires consistently moist to wet soil and may struggle in typical garden conditions.
In an HOA neighborhood
Tidalmarsh Amaranth takes more care to keep looking intentional in a front yard. Maintenance level: moderate. Consider it for backyard or mid-zone beds rather than the street edge.
Works well in: backyard only.
- Tall wild appearance looks unmanicured
- Name association with cannabis may cause neighbor concerns
- Dies back completely as annual leaving gaps
Wildlife value
This plant provides seeds for birds and serves as a host for various native insects. The flowers attract small pollinators and beneficial insects during the late summer blooming period.
Common questions
- How much sun does Tidalmarsh Amaranth need?
- Tidalmarsh Amaranth grows best in full sun conditions.
- When does Tidalmarsh Amaranth bloom?
- Tidalmarsh Amaranth blooms in July, August, and September.
- Where is Tidalmarsh Amaranth native?
- Tidalmarsh Amaranth (Amaranthus cannabinus) is native to CT, DE, FL, GA and 11 more states, per the USDA PLANTS Database and regional native plant society lists.
- Is Tidalmarsh Amaranth HOA-friendly?
- Tidalmarsh Amaranth 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 Tidalmarsh Amaranth? 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