Contrary to its name, the Australian tree fern (Cyathea cooperi, also known as Sphaeropteris cooperi) is actually more tree than fern. Typically, when we think of ferns, we envision plants such as the painted ferns (Athyrium niponicum) or autumn ferns (Dryopteris erythrosora) , which achieve a mature height of about 18 to 24 inches.
But, in its native habitat of Australia, a tree fern can grow up to 50 feet tall. This tropical plant is easily too tall for most indoor growing situations except for large conservatories and greenhouses. Still, if your space and environment allow, it can be a beautiful addition to your landscape.
Characterized by lacy, feathery fronds that grow from 10 to 20 feet in length and a hair-like, scale-covered trunk, the fast-growing, evergreen Australian tree fern can bring an exotic touch to any garden. Its best planted in the early spring and prefers warm temperatures and partial shade year-round.
With their lush, tropical-looking fronds, Australian tree ferns make a striking statement in gardens and indoor spaces But to keep your tree fern looking its vibrant best, occasional trimming and pruning are a must
Proper pruning not only maintains the fern’s aesthetic shape, but also stimulates new growth and removes potential disease vectors. Follow this in-depth guide to learn when, how, and why to trim your Australian tree fern.
Why Trimming is Essential
Here’s what regular pruning accomplishes
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Removes dead, dying, or damaged fronds. These sap the plant’s energy.
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Thins overcrowded fronds to improve air circulation and light exposure.
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Shapes and balances the fern to achieve the desired silhouette.
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Rejuvenates older plants by cutting back old fronds.
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Prevents disease by eliminating places mold and pests can gain a foothold.
When to Trim Your Tree Fern
Timing is important! The best time for pruning is late winter or early spring before new growth emerges. However, light grooming can be done year-round by removing dead fronds as needed.
Assembling Proper Pruning Tools
Before trimming, gather these essential tools:
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Hand pruners or pruning shears
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Small hand saw for thicker stems
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Gardening gloves to protect hands
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Safety goggles to shield eyes from debris
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Broom and dustpan for cleanup
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Spray bottle of disinfectant
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Trash bags for frond removal
Step-by-Step Pruning Procedure
Follow these techniques for tidy, healthy pruning:
1. Examine Entire Plant for Problem Fronds
Scan all areas of your tree fern and flag fronds that are:
- Dead, yellowed, or browning
- Damaged, broken, or limp
- Crowded, crossing, or heavily layered
- Older interior fronds that are less productive
2. Sterilize Your Cutting Tools
Wipe tools with disinfectant or diluted bleach solution before each use. This prevents transmitting diseases between fronds.
3. Remove Dead and Dying Fronds
Cut away all shriveled or discolored fronds first. Make cuts at an angle near the base to avoid trapping moisture.
4. Prune Crossing and Crowded Fronds
Selectively trim fronds that heavily drape over each other. This opens up interior circulation. But be conservative – never remove more than 20% of fronds at once.
5. Cut Back Older Interior Fronds
Pruning back some inner mature fronds near the trunk will encourage new growth underneath. Focus on fronds more than 2 years old.
6. Shape and Balance the Fern
Step back periodically and analyze shape as you prune. Trim strategically to achieve an attractive, symmetrical form.
7. Disinfect Tools After Use
Clean cutting tools with disinfectant spray again when finished pruning each plant. Remove dirt and debris with small brush.
8. Dispose of Fronds Properly
Never compost diseased trimmings. Seal them in bags and dispose of them instead. Healthy fronds can be composted or used as mulch.
Post-Pruning Care Tips
Once trimmed, care for your fern properly:
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Mist leaves after pruning to remove dust and debris.
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Water deeply to reduce transplant shock.
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Add supportive stake if pruning substantially impacted structure.
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Apply organic fertilizer to energize recovery and new growth.
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Check for signs of disease over the next few weeks.
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Consider moving indoors until new fronds emerge.
Establishing a Regular Pruning Schedule
Pruning your Australian tree fern 2-3 times per year is optimal in most climates. Some key points:
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Do major pruning in late winter or early spring.
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Groom lightly after periods of growth to remove dead fronds.
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Prune minimally in hottest summer months when growth is slower.
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Cut back frost damaged fronds after winter.
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Prune indoor ferns whenever overcrowding becomes noticeable.
Warning Signs Your Fern Needs Pruning
Watch for these cues that it’s time to prune:
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More than 3 yellowed or brown fronds visible.
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Old fronds falling off easily when touched.
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Dense internal tangle of fronds blocking air and light penetration.
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Fronds growing lopsided or disproportionate.
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White spots or fuzzy gray patches forming on leaves.
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Evidence of pests like webbing, sticky residue, or insects present.
Potential Hazards to Avoid
Steer clear of these missteps that can damage your tree fern:
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Removing too many healthy fronds at once, sending the plant into shock.
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Cutting any green, living fronds. Always prune only dead or dying fronds.
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Failing to sterilize tools between plants, spreading diseases.
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Leaving cut fronds or stubs, which invite pests and rot.
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Disturbing the root system by digging around the base.
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Pruning on hot, sunny days which stresses the plant.
With the proper tools and techniques, pruning your Australian tree fern doesn’t need to be intimidating. Stick to the guidelines in this article, and you can maintain a shapely, healthy specimen. Just remember to prune strategically, sterilize between cuts, and avoid over-pruning. With a little practice, you’ll be trimming with confidence in no time!
Propagating Australian Tree Fern
Australian tree fern can only be propagated from spores. You cannot propagate this tree fern vegetatively from cuttings.
- Collect the spores from a mature frond onto a piece of paper.
- In a heatproof bowl, pour boiling water over soilless potting medium to sterilize it and remove any pathogens, which can affect germination. Let the potting mix drain and cool completely before filling it into a four-inch pot.
- Sprinkle the spores on the potting mix and cover it with a plastic dome or bag.
- Place the pot in a location with a consistent temperature of around 68 degrees Fahrenheit and indirect light.
- Keep it moist at all times, The spores will take 2 to 6 weeks to germinate.
Types of Australian Tree Ferns
About 1,000 different kinds of tree ferns are found in tropical or subtropical settings.
- Brentwood is a cultivar that grows faster than most tree ferns and is larger with darker green fronds than the species.
- The New Zealand or Tasmanian tree fern is closely related, but the species is actually Dicksonia antarctica, and it tends to have a narrower crown than the Australian tree fern (but has similar requirements).
How to trim a Tasmanian Tree Fern
FAQ
Can I cut the top of my tree fern?
How do you reduce the height of a tree fern?
How should ferns be pruned?
How do you care for Australian tree ferns?
In addition to regular watering, Australian tree ferns thrive in moist environments. To create a humid environment, you can mist the fronds with water or place a tray of water near the plant. This will help keep the fronds healthy and prevent them from drying out. Australian tree ferns require regular feeding to maintain healthy growth.
Should fern fronds be pruned?
Yes, it is a good idea to prune brown, dead, or damaged fronds from your tree fern. This helps maintain the plant’s health and aesthetics. Always use sharp pruning shears and be careful not to damage the plant’s main stem.
How do you prune a tree fern?
Wear eye protection, long sleeves and gloves before working around the trunk and fronds of the tree fern as numerous skin-irritating hairs and scales line the fronds and stem trunk. Remove all dead fronds by making a crisp, one motion cut of the hand pruner blades 2 to 4 inches above where the frond stem attaches to the crown of the growing tip.
How do you grow a tree fern in Australia?
You can improve drainage by planting your tree fern on a slope or by adding drainage material such as gravel or sand to the soil. Australian tree ferns need ample space to grow and thrive. The plant’s mature size means that it will require plenty of room for its fronds to spread out.