Pack the crown of Tasmanian tree fern with straw before a hard freeze, and wrap the trunk with fleece or burlap, or move a pot under cover. Tasmanian tree fern is Dicksonia. Do not wrap the trunk in plastic.
Pack the crown with straw before a hard freeze, and wrap the trunk
| Factor | Recommended | Avoid |
|---|---|---|
| When | Before the first hard freeze, after you have watered the trunk | Do not wait until the crown has already frozen |
| Crown | Pack dry straw, bracken, or the plant's own fronds into the growing point | Do not leave the growing point open to a freeze, and do not soak the pack |
| Trunk | Wrap loosely with horticultural fleece or burlap | Do not wrap in plastic, which traps damp and rots the trunk |
| Mild winter | Where frost barely hits, leave an established plant in the ground | Do not wrap a plant that never sees a freeze just to have a wrap |
The growing point at the top of the trunk is what dies first in a freeze. Water the trunk and the soil, then pack the crown with dry straw, bracken, or folded fronds, and wrap the trunk with breathable fabric. [1] [2] In a garden that barely frosts, an established plant can stay in the ground and even drop its fronds, then send new ones after a cold snap. [3] Young plants and new logs need more cover than a thick, established trunk.
- Water the trunk and the soil so the plant is not dry going into a freeze.
- Pack the crown with dry straw, bracken, or the plant's own fronds. Keep that pack dry, not soggy.
- Wrap the trunk loosely with horticultural fleece or burlap. Tie it so wind cannot strip it. Skip plastic.
- In a hard freeze, add a fleece jacket over the whole crown, then take that extra layer off when the thaw comes so the pack does not rot. [4]
How cold can it take without wrapping?
An established plant in a mild garden often holds its fronds through light frost and can resprout after a harder snap. Pack the crown once a hard freeze is in the forecast.
Do I wrap it in a mild winter?
If frost barely hits, leave an established plant in the ground. Wrap when a hard freeze is coming, or if the plant is young or newly planted.
Move a pot under cover instead
A plant in a pot is easier to save than an in-ground trunk. Move it into a frost-free shed, garage, or cool conservatory before the freeze. Keep the mix moist, and keep the air from going bone-dry. A heated living room that stays dry browns the fronds. Summer the pot outside in shade once frost has passed.
- Choose a wide, heavy pot with a drainage hole, and a mix that stays moist but still drains.
- Keep the mix moist, and wet the trunk the same way you would in the garden. Empty the saucer after a soak.
- Move the pot under cover before a hard freeze. A bright, humid sunroom is better than a dry, heated room.
- Set the pot back in shade after frost, and continue on How to Grow Tasmanian Tree Fern.
Can I leave it in a pot outside?
Only if frost will not hit that pot. A container freezes faster than the ground. Move it under cover before a hard freeze, or wrap it the same way you would wrap an in-ground plant.
Unwrap in spring after frost has passed
Leave the wrap on until hard frost is done, then take it off in stages. Pull the trunk wrap first, then empty the crown pack, watching the forecast. A late freeze on a newly bared crown can kill the growing point after the plant survived the whole winter.
- Wait until hard frost has passed and daytime weather stays milder.
- Loosen the trunk wrap on a dry day, then remove it.
- Lift the straw or fleece out of the crown. Do not leave a wet pack sitting on the growing point into warm weather.
- Resume watering the trunk as new fronds start. Cut only brown fronds that the freeze killed.
When do I unwrap it?
After hard frost has passed. Unwrap in stages, and watch for a late freeze. Do not leave a wet pack on the crown into warm weather.
Pack the crown before a hard freeze, wrap the trunk with fleece or burlap, or move a pot under cover, then unwrap after frost has passed.
FAQ
Do I cut the green fronds before I wrap?
No. Leave green fronds in place. They help insulate the crown. Cut only fronds that are already brown and hanging down. Shearing the head narrows the crown over time.
Related guides
Recommended plants
References
- [1] Royal Horticultural Society -
https://www.rhs.org.uk/plants/types/ferns/tree-ferns/growing-guide - [2] BBC Gardeners' World -
https://www.gardenersworld.com/plants/dicksonia-antarctica/ - [3] San Marcos Growers -
https://www.smgrowers.com/products/plants/plantdisplay.asp?plant_id=633 - [4] The Palm Centre -
https://palmcentre.co.uk/all-on-tree-ferns/how-to-prepare-tree-ferns-dicksonia-antarctica-for-winter-in-the-uk/
This note is part of Dicksonia Guides.
More first-season notes by plant are gathered in How to Grow Guides.
Updated: Reviewed by Bosquelle Editors