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Overview
Plenogemma spp. is a genus of moss in the family Orthotrichaceae, recently separated from Ulota spp. and centered on the species Plenogemma phyllantha. It forms small, dense cushions or tufts of erect shoots, generally 0.4-1.2 inches (1-3 cm) tall, dark green to brownish, growing on tree bark, branches, and rock. The narrow leaves curl and twist when dry and spread when moist, and their tips often bear clusters of brown, club-shaped gemmae, tiny vegetative buds that break off to start new plants; this abundant production of gemmae gives the genus its name. Like all mosses, Plenogemma spp. has no true roots, flowers, or seeds, and spore capsules form only rarely in this group, so it spreads mainly by its leaf-tip gemmae. It grows in cool, humid, oceanic climates, on coastal trees and rocks exposed to clean, moist air and frequent rain or sea spray. Plenogemma spp. depends on steady atmospheric humidity and clean air, and it is absent from dry, polluted, or strongly continental areas, which narrowly limits where it occurs.
Native Range
Plenogemma spp. occurs in cool, oceanic regions of the Northern Hemisphere, including the Atlantic coasts of Europe and the Pacific and Atlantic coasts of North America. It grows on bark and rock in humid coastal woodland and on exposed shores.Suggested Uses
Grown only in specialist moss collections and humid, well-ventilated terrariums that recreate cool coastal air. In the wild it serves as an indicator of clean, humid atmospheres on coastal bark and rock.How to Identify
Appearance
Size & Dimensions
Height1"
Width/Spread4"
Bloom Information
As a moss, Plenogemma spp. does not flower. Spore capsules are rare in this group, and reproduction is mainly by the brown gemmae borne at the leaf tips, which detach and grow into new plants. These gemmae can form throughout the year in suitably humid conditions.
Detailed Descriptions
Foliage Description
Dark green to brownGrowing Conditions
Sun Requirements
Requires 1-5 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
Care & Maintenance
Care Guide
Plenogemma spp. is a wild moss of clean, humid, oceanic air rather than a routine garden plant, growing on bark and rock where atmospheric moisture is high and the air is unpolluted. It draws water and nutrients directly from rain, mist, and humidity, needing no soil or feeding. Constant humidity, good light without scorching sun, and clean air maintain the cushions, while drought, heat, and air pollution cause them to shrivel and die. In cultivation it is seen mainly in specialist moss collections and humid, well-ventilated terrariums that mimic coastal conditions. Established tufts are left undisturbed, as the gemmae spread the plant naturally onto nearby surfaces.Pruning
No pruning is needed. Surrounding surfaces are kept clear of smothering debris and competing growth. Small tufts can be moved with their bark or rock to start new colonies.Container Growing
✓ Suitable for container growing
Minimum container size: 1 gallons