Tree Fern Dicksonia Antarctica
Has the appearance if a gnarled log when dormant but fronds soon spring from the crown, growing incredibly quickly.
If given enough water the fronds will exceed the height of the trunk from which they emerge: a three foot log will produce fronds in excess of 3 and a half feet.
The trunks themselves are incredibly slow 'growing' however as they are made up of the growth from previous years. A three foot tree fern is usually in excess of 36 years old! It is for this reason that it is wise to get a specimen close to the eventual size you require, unless you are incredibly patient.
Prefers a position in a bit of shade, although I have grown them in almost full sun - basically, the more sun the more water. In the growing season a 3 foot log will take up to 3 watering cans a day!
Far hardier than often reported, the tree fern will stand down to -10 deg C without any protection but personally I would make a ball of horticultural fleece and shove this in the crown/growing point if the forecast is lower than about -8 deg C.
