Cyathea treefern hardiness in the UK?

[jbrimaco]

I have had excellent results with Dicksonia antarctica here in Vancouver Canada (USDA zone 8a/b) so decided to branch out into the genus Cyathea. I obtained spores from Tasmania for C. australis, C. medullaris, and C. cunninghamii and after 2 long years now have sporophytes (main plants) of all three species. These are still small (about 1 foot) but it's starting to look feasible to plant them our sometime in the next year or two. I know these treeferns have been attempted in Britain and was wondering if last winter's "test" has resulted in the survival in the garden of any of them. If they did survive, what protection technique (if any) did you use?

[redsquirrel]

my c.australis is still in the pot but has come through a long cold spell with 1 roll of cheap quality garden centre fleece wrapping the whole plant including the pot.all the old fronds fried but well chuffed with the results,it is miles ahead of the Dicksonia antarctica's opening new fronds

[Dave Brown]

Hi jb, and welcome to the forum

We have similar climates although seem to alternate good and bad years. It seems almost like the pole wobbles around and some winters you are under the polar airmass and others we are. I believe you have just had a very mild winter.

I only have Cyathea cooperi, which is not very hardy here even in a more normal winter. I bought it as Cyathea australis which defoliates but is supposed to be good to -10C. Apparently mislabelilng is common.

I note you are growing from spores which is quite a long winded process. I'm not sure how many members have these, particularly C medullaris as I believe the export from New Zealand was stopped, so larger specimens are not available.

I know Melissa had a C medullaris, how has your's fared Mel

[SteveW]

My cooperii came through this winter fine surprisingly,its just starting on its first crozier of the year
All I did to protect it was wrap it with fleece,must have amounted to 5 or 6 layers all told.Never expected it to come through Tbh so its a very pleasent surprise.
I think the small dealbatas okay aswell,again same treatment plus overhead cover from a Trachycarpus.

[Conifers]

I've read that Cyathea dealbata is self-regenerating (and potentially even invasive) in some Irish gardens.

[Dave Brown]

I've read that Cyathea dealbata is self-regenerating (and potentially even invasive) in some Irish gardens.

Sounds good to me

[redsquirrel]

heres my australis,put it in the tunnel incase of frost while we were away and came back to find this

[Nigel Fear]

That Cyathia's excellent Darren!
How long have you had that, does the trunk grow reasonably quick?

[bev]

looking good darren, i didn't know you had a tunnel


cheers

lee

[redsquirrel]

shh,we have 2 up at the moment,the other one will come down soon but this one stays up to keep the wind and rain off a few bits

[skelding]

I have been growig tree ferns in the UK for ten years now and I have to say that Cyatheas are not a realistic option for growing out doors in the UK.

I have imported trunked specimens of Dealbata (four footer), Smithii (four footer), Australis (six footer), Medullaris (two footers), cunninghamii (one footer) and they all struggled for a few years before passing to that great tree fern heaven. So I tried spore of all the above and many other rarities from Australia, Borneo and other Southern Asian regions, they like wise grew happily for a few years (with plenty of winter protection) before falling foul of our winters.

C Australis was the best survivor, lasted for around six years before if passed away last winter.

I have a cooperi that has survived in a pot, overwinter in my garage, for nearly nine years. But I have never had the courage to plant it outside as it is a stunner.

I even lost a D. fibrosa last winter that has survived for the last ten years.

Dicksonia antarctica are as tough as old boots and shrug off all the UK can throw at them, I still have specimens upto 12 feet tall.

Sorry to sound so pessimistic, but I have been trying for ten years plus without much long term success....

[Dave Brown]

Did you give any protection to the ones you lost Nick We have had a 1 in 20, followed by a 1 in 30 year winter. Would it be feisable to get by with fleece in the colder winters

[metalhammer]

Lost all 3 of my australis in the last,1 in 20 year winter.If I do start again,it will be with seedlings not trunks.





metalhammer.

[redsquirrel]

losing a fibrosa must have been a surprise shock after those years gone by.i have a number of Dicksonia antarctica and a couple of fibrosas.should say 'had' a couple of fibrosas.one went all gooey and gunky with the yuck dripping out yet the other is my only fern to have remained green. ive given up on marginal hardiness reports now as it seems a lot of it has to do with individual plants.for example,my capitata out in the open with a rain shelter didnt mark at -10 yet a reasonably c.humilis only 3 ft away behind a south facing wall spear pulled and looks rubbish.id at least have expected the butia to have shown some browning even if it was under a cover,it still endured the same temps

[skelding]

All my cyatheas were protected with horticultural fleece and straw all round the trunk, except the australis which seem to be fine with an upended hanging basket stuffed full of straw. I find that the protection has to offer protection from the freezing cold and wet, but it also has to be breathable or crown rot sets in, but this is not an exact science

The australis can be seen second on the left here



I have two fibrosa, one is around nine foot tall and that seems fine, the other is around 4~5 foot, it was hit hard last winter and I thought I had lost it, but it did push out four "mini fronds", but I can't feel any nuckles in the crown at all this year, but I will give it another six months in case. I leave all the old fronds on my Dfsto give extra crown protection. Will take a photo of the biggie if anybody would like to see?