Photo: naturewatchwidowCC BY 4.0via iNaturalistresized / cropped
Colenso's tree fern Plant Care
Alsophila colensoi Hook.f.
Updated · Sources · How we source care data
With its striking, large fronds that can reach up to 3 meters in length, this fern species originating from New Zealand is a showstopper in any garden. Plant collectors are drawn to Alsophila colensoi for its impressive size and unique architectural presence, making it a sought-after addition to any botanical collection.
Every 7–14 days
Bright indirect to low light
60–80°F
60–80%
At a glance
How do you care for Colenso's tree fern?
Water Colenso's tree fern every 7–14 days, letting the top layer of soil dry out between waterings, and give it bright indirect to low light. It prefers temperatures of 60–80°F (16–27°C) and 60–80% humidity. Fertilize it every 6 months during the growing season.
Where Is the Colenso's tree fern Native To?
What Is the Colenso's tree fern?
Colenso's tree fern (Alsophila colensoi) belongs to the Cyatheaceae family within the Alsophila genus. Colenso's tree fern is native to New Zealand, from the southern part of the North Island south to Stewart Island.
Colenso's tree fern displays a large, tree-like fern growth habit, reaching up to 10 ft tall with a spread of approximately 5 ft. Colenso's tree fern produces non-flowering.
Leaf size: approximately 36 inches.
How Often Should You Water a Colenso's tree fern?
Alsophila colensoi 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 Colenso's tree fern Need?
Colenso's tree fern thrives in bright indirect to low light. Avoid placing Colenso's tree fern in direct, harsh sunlight for extended periods, as this can scorch the foliage.
Light Requirement
Bright indirect to low light
What Temperature and Humidity Does the Colenso's tree fern Prefer?
Alsophila colensoi grows best at temperatures of 60–80°F. Colenso's tree fern prefers humidity levels of 60–80%. A pebble tray or humidifier helps maintain adequate moisture around the plant.
Temperature
60–80°F
Humidity
60–80%
What Soil Mix Works Best for a Colenso's tree fern?
Rich, well-draining soil with high organic content. Good drainage is essential for Colenso's tree fern to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Colenso's tree fern?
Feed Colenso's tree fern every 6 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 6 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 Colenso's tree fern?
Repot every 2-3 years. 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 Colenso's tree fern?
Colenso's tree fern can be propagated through spores. Similar propagation techniques also apply to tree fern plant care, which shares the same genus.
Is the Colenso's tree fern Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Colenso's tree fern, 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 Colenso's tree fern?
Colenso's tree fern 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 Colenso's tree fern Need?
Colenso's tree fern grows outdoors in USDA Zone 8a – 9b. It survives winters down to planting zone 8a. Colenso's tree fern is native to New Zealand, from the southern part of the North Island south to Stewart Island.
Hardiness Zone
Zone 8a – 9b
Keep exploring plants
Colenso's tree fern 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 Alsophila genus — compare its care with other Alsophila species on PlantoScan.
Alsophila is part of the Cyatheaceae plant family — browse all Cyatheaceae genera and species.
Colenso's tree fern copes with lower light than most plants — browse the full list of low-light plants.
More Alsophila Species
Other Alsophila species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Alsophila colensoi Hook.f., family Cyatheaceae (first published in Fl. New Zealand 2. 8 (1854)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Colenso's tree fern, 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.
- Photo: naturewatchwidow, CC BY 4.0, iNaturalist — original.
- Hardiness zone: USDA Zone 8a – 9b, estimated from the plant's typical growing conditions.
- 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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