I'd say that it is more than likely wind damage, but it could also be the
seaweed feeding if it is high in phosphorus.
In their natural habitat these ferns prefer to live in gullies and usually
under the canopy of trees so they wouldn't get much wind but could get very
cold conditions (down to -10 C where I know they do grow well).
I wish I could show you a wild area near me where they grow by their 10s of
thousands in just such a state. Glorious, glorious, glorious. Like a
cathedral without the dogma and cant.
This area is quite moist and is known as 'wet sclerophyll' forest but
Dicksonia antarctica can also survive quite well for some time in dry
conditions.
Most internet sites will no doubt tell you that they like fertile moist soil
but remember that Australia is deficient in phosphorus, our 'fertile' will
not be the same as a Brits definition of fertile and plants here have
learned to survive with low levels of many nutrients and especially
phosphorus - think perhaps high fibre such as leaf litter rather than NPK.
Check the seaweed feeed for its phosphorus content in particular.
Brits (from what I've learned of then reading ngs for years) tend to both
overfeed and overwater Australian natives and then, the plant grows like
Topsy but isn't long lived.
The best way to water a Dicksonia Antarctica is to put a dripper in the
crown and don't bother about the trunk - the crown is the vital bit. Also
the advice given here is to put a tspn of sugar in the crown once a month -
dunno why but that has been widely bandied about.
If I were you, I'd be thinking about phosphorus, wind, and how much sunlight
its getting - I wouldn't worry about cold so much (but it could be a factor
but I have doubts). Day length is much longer in the UK than in Oz and
although our levels of radiation are probably much more fierce than yours,
these plants get less day length than in the UK. |