Great Haircap Moss Plant Care
Polytrichastrum formosum (Hedw.) G.L.Sm.
Updated · Sources · How we source care data
Polytrichastrum formosum, commonly known as the bank haircap moss, is a species of moss belonging to the family Polytrichaceae.
Every 7–14 days
Bright indirect to partial shade
60–75°F
50–70%
At a glance
How do you care for Great Haircap Moss?
Water Great Haircap Moss every 7–14 days, letting the top layer of soil dry out between waterings, and give it bright indirect to partial shade. It prefers temperatures of 60–75°F (16–24°C) and 50–70% humidity.
What Is the Great Haircap Moss?
Great Haircap Moss (Polytrichastrum formosum) belongs to the Polytrichaceae family within the Polytrichastrum genus. Great Haircap Moss is also known as Common Haircap Moss, Pincushion Moss.
Great Haircap Moss displays a low rosette, spreading mat growth habit, reaching up to 0.1 ft tall with a spread of approximately 0.5 ft. Great Haircap Moss produces non-flowering.
Leaf size: approximately 1 inches.
How Often Should You Water a Great Haircap Moss?
Polytrichastrum formosum requires watering every 7–14 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.
Watering Frequency
Every 7–14 days
Let soil partially dry between waterings
What Light Does the Great Haircap Moss Need?
Great Haircap Moss thrives in bright indirect to partial shade. Avoid placing Great Haircap Moss in direct, harsh sunlight for extended periods, as this can scorch the foliage.
Light Requirement
Bright indirect to partial shade
What Temperature and Humidity Does the Great Haircap Moss Prefer?
Polytrichastrum formosum grows best at temperatures of 60–75°F. Great Haircap Moss prefers humidity levels of 50–70%. A pebble tray or humidifier helps maintain adequate moisture around the plant.
Temperature
60–75°F
Humidity
50–70%
What Soil Mix Works Best for a Great Haircap Moss?
Well-draining acidic soil with high organic matter content. Good drainage is essential for Great Haircap Moss to prevent waterlogging, which leads to root rot and fungal issues.
How Do You Repot a Great Haircap Moss?
Repot every 2-3 years in early spring. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.
How Do You Propagate a Great Haircap Moss?
Great Haircap Moss can be propagated through spores, division of clumps. Similar propagation techniques also apply to alpine haircap moss plant care, which shares the same genus.
Is the Great Haircap Moss Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Great Haircap Moss, so we can't confirm whether it is safe for cats and dogs. Keep pets from chewing it as a precaution.
This is a general caution, not veterinary or medical advice. If your pet ate a plant, contact your vet or animal poison control.
See all plants toxic to cats and plants toxic to dogs.
What Pests and Diseases Affect the Great Haircap Moss?
Great Haircap Moss is susceptible to generally pest-resistant. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.
Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.
What USDA Hardiness Zone Does the Great Haircap Moss Need?
Great Haircap Moss grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. In cooler regions, grow Great Haircap Moss as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 13a
Keep exploring plants
Great Haircap Moss is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.
It belongs to the Polytrichastrum genus — compare its care with other Polytrichastrum species on PlantoScan.
Polytrichastrum is part of the Polytrichaceae plant family — browse all Polytrichaceae genera and species.
Great Haircap Moss thrives in bright light and direct sun — see other bright-light plants.
Related Plant Care Guides
Closely related plants with similar care requirements:
Sources
- Scientific name & taxonomy: Polytrichastrum formosum (Hedw.) G.L.Sm., family Polytrichaceae (first published in Mem. New York Bot. Gard. 21(3): 37 1971) — World Flora Online record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Great Haircap Moss, so we can't confirm whether it is safe for cats and dogs. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
- Hardiness zone: USDA Zone 13a, calculated from the plant's minimum temperature.
- Care values(watering, light, temperature, humidity, soil, fertilizing): PlantoScan's plant database, filtered by automatic plausibility checks — values that fail them are hidden. How we source and check plant data.
Spotted a mistake? Email info@upvision.media with the page link — we check and correct reported errors.
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