Supine Bluegrass: A Cool-Climate Ground Cover Worth Considering
If you’re searching for an unusual grass that thinks outside the box—or rather, outside the typical lawn—supine bluegrass (Poa supina) might just catch your attention. This European native has some interesting tricks up its sleeve that make it quite different from your average turf grass.
What Exactly Is Supine Bluegrass?
Supine bluegrass is a low-growing, fine-textured grass that belongs to the graminoid family (that’s fancy talk for grass-like plants). True to its name, this grass has a supine or reclining growth habit, meaning it spreads horizontally to form dense, carpet-like mats rather than growing tall and upright like traditional lawn grasses.
The soft, green foliage creates an almost cushion-like appearance that’s quite appealing to the eye. While it may not win any height contests, what it lacks in stature, it makes up for in coverage and texture.
Where Does It Come From?
This cool-season grass hails from Europe, particularly thriving in the cooler regions of Scandinavia and northern and central European countries. It’s adapted to climates that experience distinct seasons with cool, moist conditions—which gives us a big hint about where it’ll be happiest in North American gardens.
Is Supine Bluegrass Right for Your Garden?
Here’s where things get interesting. Supine bluegrass isn’t your typical lawn substitute, but it could be perfect for specific situations:
- Rock gardens and alpine settings: Its low, mat-forming habit makes it ideal for tucking between rocks or covering difficult slopes
- Cool-climate landscapes: If you live in USDA zones 3-7, this grass will feel right at home
- Erosion control: Those dense mats are excellent for holding soil in place on gentle slopes
- Low-traffic areas: Perfect for areas where you want green coverage but don’t need to walk on it regularly
Growing Conditions: Keep It Cool and Comfortable
Supine bluegrass has some specific preferences that you’ll want to keep in mind:
- Temperature: Thrives in USDA hardiness zones 3-7; struggles in hot, humid climates
- Sunlight: Handles partial shade better than many grasses, though it also does well in full sun in cooler climates
- Soil: Prefers well-draining soil but needs consistent moisture
- Climate: Cool, moist conditions are ideal—think Pacific Northwest or northern states
Planting and Care Tips
Getting supine bluegrass established requires a bit of patience, but it’s not particularly fussy once it gets going:
- Best planting time: Early spring or fall when temperatures are cool
- Establishment: Start from seed and keep consistently moist during germination
- Maintenance: Low maintenance once established, requiring minimal fertilization
- Watering: Regular watering during dry spells, especially in summer
- Mowing: Rarely needs mowing due to its low growth habit
Wildlife and Pollinator Considerations
As a wind-pollinated grass, supine bluegrass doesn’t offer much in the way of nectar or pollen for bees and butterflies. However, like many grasses, it can provide habitat for small beneficial insects and ground-dwelling creatures.
The Native Alternative Question
Since supine bluegrass isn’t native to North America, you might want to consider native alternatives that could provide similar benefits. Depending on your region, native sedges, buffalo grass, or other indigenous ground covers might give you comparable results while supporting local ecosystems.
Some native alternatives to consider include various Carex species (sedges) for similar low-growing coverage, or native bunch grasses that can provide textural interest in naturalized settings.
The Bottom Line
Supine bluegrass is an interesting option for gardeners in cooler climates who want something different from traditional turf. Its low, mat-forming habit and tolerance for partial shade make it useful for specific landscape situations. While it won’t replace your main lawn, it could be perfect for those tricky spots where you need reliable ground cover with minimal maintenance.
Just remember: this grass prefers to keep its cool, so if you’re gardening in hot, humid climates, you might want to look elsewhere for your ground cover needs.
