American rock brake Plant Care
Cryptogramma acrostichoides R.Br.
Updated · Sources · How we source care data
Cryptogramma acrostichoides is a fern species in the Cryptogrammoideae subfamily of the Pteridaceae. It is known by the common names American parsley fern and American rockbrake and is native to most of western North America, where it grows in the cracks of rocks in many types of sunny mountainous habitat.
Every 4–7 days
Partial to full shade
50–75°F
60–80%
At a glance
How do you care for American rock brake?
Water American rock brake every 4–7 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. Fertilize it every 8 months during the growing season.
Where Is the American rock brake Native To?
What Is the American rock brake?
American rock brake (Cryptogramma acrostichoides) belongs to the Pteridaceae family within the Cryptogramma genus. American rock brake is native to most of western North America. American rock brake is also known as Rock brake, Parsley fern.
American rock brake displays a low rosette, spreading growth habit, reaching up to 0.5 ft tall with a spread of approximately 1 ft. American rock brake produces non-flowering.
Leaf size: approximately 6 inches.
How Often Should You Water a American rock brake?
Cryptogramma acrostichoides requires watering every 4–7 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 4–7 days
Let soil partially dry between waterings
What Light Does the American rock brake Need?
American rock brake thrives in partial to full shade. The optimal light range is 100–500 lux. Avoid placing American rock brake in direct, harsh sunlight for extended periods, as this can scorch the foliage.
Light Requirement
Partial to full shade
100–500 lux
What Temperature and Humidity Does the American rock brake Prefer?
Cryptogramma acrostichoides grows best at temperatures of 50–75°F. American rock brake 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 American rock brake?
Well-draining, acidic soil with high organic matter content. Good drainage is essential for American rock brake to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a American rock brake?
Feed American rock brake every 8 months during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.
Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.
Fertilizing
Every 8 months
During the growing season
The PlantoScan app can remind you when to water and when to fertilize each plant.
How Do You Repot a American rock brake?
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 American rock brake?
American rock brake can be propagated through spores.
Is the American rock brake Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list American rock brake, 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 American rock brake?
American rock brake is susceptible to spider mites, scale insects. 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 American rock brake Need?
American rock brake grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. American rock brake is native to most of western North America. In cooler regions, grow American rock brake as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
American rock brake 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 Cryptogramma genus (family Pteridaceae) — search all Cryptogramma species in the plant lookup.
American rock brake 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: Cryptogramma acrostichoides R.Br., family Pteridaceae (first published in Narr. Journey Polar Sea 767 (-768) (1823)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list American rock brake, 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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