Slough Grass
Beckmannia syzigachne
Last reviewed: September 2026
Beckmannia syzigachne, known as American sloughgrass, grows in wet meadows, marshes, ditches, and pond edges, blooming from June through August with slender spike-like seed heads.
Toxicity unknown
Slough Grass (Beckmannia syzigachne) 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.
The USDA PLANTS Database (opens in new tab) does not flag Slough Grass as toxic to livestock.
Light
full sun
Water
high
Size
12"–36" H × 6"–18" W
Bloom
Jun, Jul, Aug
Native to
AZ, CA, CO, IA and 20 more states
Before you buy
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Slough grass is a native wetland grass that forms upright clumps with narrow leaves and delicate seed heads in summer. It requires consistently moist to wet soil conditions and thrives in full sun locations. This cool-season grass goes dormant in winter, turning brown before new growth emerges in spring.
Growing Slough Grass
Grow Slough Grass in full sun and high water. Mature plants reach 12 to 36 inches tall and spread 6 to 18 inches wide. Expect moderate maintenance to keep it looking intentional in a front yard.
In an HOA neighborhood
Slough Grass 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.
- Requires wet soil conditions that may cause drainage concerns
- Can look weedy and unkempt during dormant season
- Associated with wetland areas rather than maintained landscapes
Wildlife value
This grass provides nesting material and cover for waterfowl and marsh birds. The seeds feed various songbirds and waterfowl in late summer and fall.
Common questions
- When does American sloughgrass bloom?
- Beckmannia syzigachne blooms from June through August, sending up tall stems topped with narrow, spike-like seed heads.
- What conditions does slough grass need to grow well?
- It grows best in full sun to part sun and needs consistently wet to moist soil, which is why it is often found in ditches, marshes, and seasonally flooded meadows.
- Can slough grass handle drier soil for part of the year?
- It tolerates some seasonal drying but performs best where soil stays moist to saturated for most of the growing season.
- Is Slough Grass toxic to livestock?
- The USDA PLANTS Database does not flag Slough Grass as toxic to livestock.
- Is Slough Grass HOA-friendly?
- Slough Grass takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.
These answers were drafted with an AI model from this plant's data. Verify care details with a local expert.
Native range data from the World Checklist of Vascular Plants (Kew). 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 Slough Grass? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.
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