Overview
Grimmia laevigata is a small, cushion-forming moss that grows in dense, rounded tufts on exposed rock. The cushions are 0.4-1.5 inches (1-4 cm) across and dark olive to blackish-green when moist, turning grey-green and hoary when dry. Each tiny leaf, about 0.08-0.16 inch (2-4 mm) long, ends in a long, clear, glassy hair point, and these white tips give a dry cushion its frosted look. The plant lacks true roots and draws water directly across its surfaces, anchoring to rock by slender holdfasts rather than feeding roots. It is strongly desiccation tolerant, drying to a dormant state in drought and reviving within minutes of wetting. Spore capsules are small and held on short stalks among the leaves, releasing spores in the cooler, wetter season. The species grows on dry, sun-exposed granite, sandstone, and other hard rock across much of the world, including North America, Europe, and beyond. A limitation for cultivation is its strict attachment to bare rock, since it does not grow in soil or tolerate constant moisture and deep shade.
Native Range
Grimmia laevigata has a broad, nearly cosmopolitan range, occurring on exposed rock across North America, South America, Europe, Africa, Asia, and Australia. In North America it is widespread from Canada through the United States into Mexico.Suggested Uses
Grown on rock gardens, stone walls, boulders, and moss gardens for low, weathered green cushions on exposed stone. Suited to sunny, dry rock surfaces where most plants cannot root. The cushions help hold thin films of grit on rock and add texture to hardscape.How to Identify
Growing Conditions
Sun Requirements
Requires 6-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Water & Climate
Water Needs
Drought Tolerance
Drought tolerant when established
Care & Maintenance
Care Guide
Grimmia laevigata grows on bare, sun-exposed rock and needs no soil, drawing moisture directly from rain, dew, and humidity. It is established by pressing fragments or cushions onto clean, rough stone in an open, sunny position. The moss tolerates extreme heat, drying, and full sun, drying to dormancy and reviving when wetted. Constant moisture, deep shade, or a covering of soil and litter cause it to decline. On rock or stone surfaces it needs only occasional wetting during long dry spells.Container Growing
Suitable for container growing
Minimum container size: 1 gallons
