Replant it immediately. Dig out all the manure and soil
mix you used. Got any commercial azelea mix? Get that and get some shredded bark or even fine ground cover bark and mix the azelea mix and bark at 50/50 and then replant your fern using this mix.
My initial thought was that it is too cold for the fern but when you mentioned manure then what may have happened is that the fern has not rooted into the soil as its roots may be being burned to death by the manure and so when the new growths go so high there is not enough root growth to support any substantial growth.
Replant and save the manure for vegetable gardens!

Thanks for that. Re-planted using azelea and bark mix. Now keeping my fingers crossed.

To give you a heads up on where the plant should be under
normal conditions:
Fall is coming. Last years leaves will have or will be turning brown and can be cut off. This years new leaves which began growing sometime in mid summer should be close to maximum size.
Since the stem of the fern is actually rhizomes that can absorb water I would make it a point to water the stem though not necessarily the growing crown. Humidity around the plant may be helpful in its recovery. But I would not allow the soil to stay wet. Water the growing stem and let that water soak into the soil.
With the weather do not expect anything other than a slow recovery but this can be one tough plant so give it time.

Azalea mix in this country (the UK) tends to be a gravelly loam with a fairly powerful base fertilizer added. For the same reasons your previous regime was deadly, you may well struggle all over again. I wouldn't be happy having that near my ferns. A proven compost mixture that I've used for a decade on all kinds of tree ferns is a 50:50 blend of proprietary ericaceous compost (either peaty J.Arthur Bowyer's or bark-based Levington's...but not loam or John Innes) and bark-based multi-purpose compost (such as Bowyer's New Horizon). Bulking up this mixture with leaf mould, well-rotted garden compost and your regular topsoil will make a very acceptable tree fern planting medium. Lots of trunk watering is desirable - and in the warmest part of the growing season, flooding the crown every day may be required to maintain sufficient moisture. Hold off in winter, though, unless it's persistently dry and mild. And no powerful fertilizer feeds, like tomato feed! Tree ferns are primarily nitrogenous feeders and live off decomposing organic matter from the forest floor and the canopy above. So try and keep nutrient gentle, slow acting and organic.

Wow Stephenpope thanks for the heads up on the UK Azelea mix.
Is not at all like the stuff I use here in California, which looks closer to a leaf mould than the gravelly loam
you describe!!

Below is a link of a garden center in the UK for infomration on growing azeleas and rhodies!

Here is a link that might be useful: Advice on azalea culture

Yes, our loam-based azalea mix tends to be very strong stuff over here in the UK, whereas the US equivalent sounds like it would be fine straight out of the packet for ferns. I'm sure rhodos and azaleas would equally love a good ericaceous fern compost...but not the other way round if it's a John Innes type product.

Another potential explanation for the original poster's problem with their tree fern - quite apart from compost issues - is that new phytosanitary and quarantine restrictions have resulted in much more debilitated Dicksonia antarctica trunks reaching the import market. Where they were once just salvaged and shipped out for a fast buck, these trunks now have to be blitzed with highly aggressive chemical insecticides and then be stockpiled in an Australian holding nursery for an additional year before export...probably with minimal care in order to keep costs down. That regime inevitably takes its toll on already highly stressed plants. No wonder so many of our more recent garden tree fern purchases are now failing, in comparison to the near 100 per cent re-establishing rate with the old stock. It's nowhere near as foolproof as it used to be.

It's quite possible the ailing tree fern being described in the first post is simply too damaged from the whole export ordeal - and that changing the planting conditions at this late stage will make no difference.

Local forms of Dicksonia occur on dense acidic clays (yellow-brown), often overlain with fine duff from evergreen plants which shed leaves just before new growth in spring, or earlier, if the winter has been dry. They, and their Aussie counterpart, spread their 'roots' at least 1.5m out from the stem. There's very little that can compete with that growth, too. They grow very well in the ecotone at the edge of pine plantations where they can enjoy the wind protection along with the mulching from fallen needles.

If the plant is not recovering in the garden then it could be worth potting it up in a biggish container. Young tree ferns are often sold bagged here, or container-grown. The usual mix can be either a standard pine-bark brew with some pumice for drainage and a small amount of slow-release but no water crystals, or a silty clay mix.

Should it look as if it has gasped its last, before consigning to wherever, lay it down and partly earth up around it. Maybe a third of the trunk diameter. Sometimes it will resprout from along the trunk and continue growing from there. Know, however, that the root system will be pretty shallow for several years to come so cultivate with great care.

Mulch with pine needles, perhaps Eucalyptus leaves, part rotted, and/or deciduous leaves shredded and mixed with ancient softwood sawdust with a touch merely of blood and bone. Old rotted wood - even small rotting branches laid on the ground - can help to keep the area cool and slowly release a useful mixture into the top layer.

Aside: a few years back I rested a tree fern slab against the trunk of D antarctica and forgot it. When I next looked the living tree fern's trunk was slowly engulfing the slab. Guess I won't be growing the stagshorn on that one!

Hi
I have a four foot fern which has has survived the winter with all fronds intact. just wondering do I cut the frond off for the new ones to grow for summer or just leave them..I am guessing I just leave them on unless they die off