Bristle-cap Moss Plant Care

Polytrichum piliferum Hedw.

Updated · Sources · How we source care data

Polytrichum piliferum, the bristly haircap, is an evergreen perennial species of moss in the family Polytrichaceae. The bristly haircap moss is small-sized to medium-sized and forms loose tufts with wine-reddish stems.

Water

Every 3–7 days

Light

Partial to full shade

Temp

50–75°F

Humidity

60–80%

At a glance

How do you care for Bristle-cap Moss?

Water Bristle-cap Moss every 3–7 days, letting the top layer of soil dry out between waterings, and give it partial to full shade. It prefers temperatures of 50–75°F (10–24°C) and 60–80% humidity.

What Is the Bristle-cap Moss?

Bristle-cap Moss (Polytrichum piliferum) belongs to the Polytrichaceae family within the Polytrichum genus. Bristle-cap Moss is also known as Haircap Moss, Pincushion Moss.

Bristle-cap Moss displays a low mat-forming growth habit, reaching up to 0.1 ft tall with a spread of approximately 0.5 ft. Bristle-cap Moss produces non-flowering.

Leaf size: approximately 2 inches.

How Often Should You Water a Bristle-cap Moss?

Polytrichum piliferum requires watering every 3–7 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 3–7 days

Let soil partially dry between waterings

What Light Does the Bristle-cap Moss Need?

Bristle-cap Moss thrives in partial to full shade. The optimal light range is 50–200 lux. Avoid placing Bristle-cap Moss in direct, harsh sunlight for extended periods, as this can scorch the foliage.

Light Requirement

Partial to full shade

50–200 lux

What Temperature and Humidity Does the Bristle-cap Moss Prefer?

Polytrichum piliferum grows best at temperatures of 50–75°F. Bristle-cap Moss prefers humidity levels of 60–80%. A pebble tray or humidifier helps maintain adequate moisture around the plant.

Temperature

50–75°F

Humidity

60–80%

What Soil Mix Works Best for a Bristle-cap Moss?

Well-draining acidic soil with high organic content. Good drainage is essential for Bristle-cap Moss to prevent waterlogging, which leads to root rot and fungal issues.

How Do You Repot a Bristle-cap Moss?

Rarely requires repotting. 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 Bristle-cap Moss?

Bristle-cap Moss can be propagated through spores. Similar propagation techniques also apply to common haircap moss plant care, which shares the same genus.

Is the Bristle-cap Moss Toxic to Pets and Children?

Pet safety not verified

The ASPCA does not list Bristle-cap 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 Bristle-cap Moss?

Bristle-cap 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 Bristle-cap Moss Need?

Bristle-cap Moss grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. In cooler regions, grow Bristle-cap Moss as a houseplant or bring it indoors before the first frost.

Hardiness Zone

Zone 12a

Keep exploring plants

Bristle-cap 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 Polytrichum genus — compare its care with other Polytrichum species on PlantoScan.

Polytrichum is part of the Polytrichaceae plant family — browse all Polytrichaceae genera and species.

Bristle-cap Moss copes with lower light than most plants — browse the full list of low-light plants.

Related Plant Care Guides

Closely related plants with similar care requirements:

Sources

  • Scientific name & taxonomy: Polytrichum piliferum Hedw., family Polytrichaceae (first published in Sp. Musc. Frond. 90 1801) — World Flora Online record.
  • Pet toxicity: Pet safety not verified: the ASPCA does not list Bristle-cap 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 12a, 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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