Mertens' Sedge
Carex mertensii
Last reviewed: August 2026
Mertens' Sedge (Carex mertensii) is a perennial forb native to CA, ID, MT, OR and 1 more states. It blooms in May, June, and July. It reads as an intentional, HOA-friendly planting in the right spot.
Toxicity unknown
Mertens' Sedge (Carex mertensii) 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 Mertens' Sedge as toxic to livestock.
Light
part shade
Water
medium
Size
8"–24" H × 6"–12" W
Bloom
May, Jun, Jul
Native to
CA, ID, MT, OR and 1 more states
Before you buy
Your city may pay you to plant this
Cities and water utilities offer rebates for replacing lawn with native and water-wise plants. We track 437 programs across 44 states, each with a link to the provider and the date we last checked it.
Find rebates in your areaBrowse plants for this ecoregion
Mertens' sedge is a clumping grass-like perennial that forms neat tufts of narrow green leaves. This native sedge thrives in partial shade with moderate water, producing small flower spikes in late spring and early summer. It maintains a tidy, compact appearance throughout the growing season.
Growing Mertens' Sedge
Grow Mertens' Sedge in part shade and medium water. Mature plants reach 8 to 24 inches tall and spread 6 to 12 inches wide. Expect low maintenance to keep it looking intentional in a front yard.
In an HOA neighborhood
Mertens' Sedge is an HOA-friendly choice. Maintenance level: low. Tidiness: 4 out of 5.
Works well in: front yard, foundation, street edge, mid zone.
Wildlife value
This sedge provides habitat and nesting material for small birds and beneficial insects. The seeds offer food for songbirds and small mammals in late summer and fall.
Common questions
- How much sun does Mertens' Sedge need?
- Mertens' Sedge grows best in part shade conditions.
- When does Mertens' Sedge bloom?
- Mertens' Sedge blooms in May, June, and July.
- Where is Mertens' Sedge native?
- Mertens' Sedge (Carex mertensii) is native to CA, ID, MT, OR and 1 more states, per vouchered herbarium specimen records and regional native plant society lists.
- Is Mertens' Sedge toxic to livestock?
- The USDA PLANTS Database does not flag Mertens' Sedge as toxic to livestock.
- Is Mertens' Sedge HOA-friendly?
- Mertens' Sedge is generally an HOA-friendly choice in the right placement, with low maintenance.
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.
Ready to grow Mertens' Sedge? 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