German Knotgrass: A Tiny Ground Cover with Big Personality
If you’ve ever wondered about those tiny, almost moss-like plants growing in sidewalk cracks or rocky areas, you might have encountered German knotgrass (Scleranthus). This unassuming little plant might not win any beauty contests, but it has earned its place in gardens around the world through sheer determination and adaptability.
What Exactly Is German Knotgrass?
German knotgrass belongs to the Scleranthus genus and is technically classified as a forb—basically a non-woody plant that stays close to the ground. Don’t let the grass in its common name fool you; this little survivor is actually more closely related to carnations than to your lawn. It can be either annual or perennial, depending on the specific species and growing conditions.
The plant forms dense, cushion-like mats with tiny, needle-like leaves that create an almost moss-like appearance. Its flowers are so small you might miss them entirely—they’re tiny, greenish clusters that appear more like little knots (hence the knotgrass name) than traditional flowers.
Where Does It Come From and Where Can You Find It?
Here’s where things get interesting: German knotgrass isn’t actually native to North America. This European transplant has made itself quite at home across the continent, establishing populations from coast to coast. You can find it growing in an impressive range of locations, including Alberta, British Columbia, and most Canadian provinces, as well as states from California to Maine and everywhere in between.
As a non-native species that reproduces and persists without human intervention, German knotgrass falls into that gray area of plants that aren’t necessarily harmful but aren’t native either. It’s naturalized so successfully that many people assume it belongs here.
Why Would You Want (or Not Want) This Plant?
German knotgrass isn’t going to be the star of your flower border, but it has some genuine merits:
- Extremely drought tolerant once established
- Thrives in poor, sandy, or gravelly soils where other plants struggle
- Forms dense ground cover that can suppress weeds
- Requires virtually no maintenance
- Perfect for rock gardens and xerophytic landscapes
- Can grow between stepping stones or in pavement cracks
On the flip side, its benefits are limited when it comes to supporting local wildlife. The tiny flowers offer minimal value to pollinators, and the plant doesn’t provide significant food or habitat for native creatures.
Growing German Knotgrass Successfully
If you decide to grow German knotgrass, you’ll be pleased to know it’s nearly foolproof. This plant actually prefers neglect over pampering.
Ideal Growing Conditions
- Sunlight: Full sun is best, though it tolerates partial shade
- Soil: Well-draining, sandy, or gravelly soils; avoid rich, moist conditions
- Water: Drought tolerant; overwatering is more likely to kill it than drought
- Hardiness: Generally hardy in USDA zones 3-9
Planting and Care Tips
German knotgrass is so adaptable that it often establishes itself without any help. If you’re intentionally planting it:
- Scatter seeds in early spring or fall on prepared soil
- Barely cover seeds—they need light to germinate
- Water lightly until established, then let nature take over
- No fertilizer needed—it actually prefers poor soils
- Trim back if it spreads beyond desired areas
Consider Native Alternatives
While German knotgrass isn’t harmful, supporting native plants is always a great choice for local ecosystems. Consider these native alternatives that offer similar ground-covering abilities:
- Wild strawberry (Fragaria species) for shaded areas
- Native sedums for sunny, dry spots
- Moss phlox (Phlox subulata) for colorful spring coverage
- Regional native grasses for larger areas
The Bottom Line
German knotgrass is like that reliable friend who’s always there when you need them—not flashy, but dependable. It’s perfect for challenging spots where other plants fail, and it asks for almost nothing in return. While it won’t support native wildlife like indigenous plants would, it’s not invasive enough to cause ecological problems either.
Whether you choose to embrace this humble ground cover or opt for native alternatives, remember that every garden is unique. Sometimes the best plant for a particular spot is simply the one that will thrive there with minimal fuss—and German knotgrass certainly fits that bill.
