Cyathea dregei is a rather large, stout-trunked tree fern from the forests and grasslands South Africa, Madagascar and other parts of east Africa.  It seems to have made it into culativation just recently in Europe, but is largely unknown in the United States.  It is of great interest for several reasons.

It grows over a large area in which the climate ranges from temparate to tropical, and areas with dry winters and wet summers as well as areas that are the other way around (the western Cape).  Some of this region is surprisingly arid and hot, yet this treefern is usually found growing out in the open in full sun (somewhat like C. australis), though always near streambanks or in sites where it can get a constant supply of soil moisture.  In addition to summer heat, it must also tolerate severe winter frosts and snow.  Because of the open situations which it chooses to inhabit, it is subjected to the full effect of the frost without the benefit of an overhead canopy.  It is also described as "deciduous," and though this is probably not technically correct, it seems that this treefern does not mind losing its fronds and growing them back as much as other treeferns do.  The fronds can be damaged from temperatures as high as 30°F, and most winters in South Africa they are, but with no lasting ill effect to the plant.

Because of its large natural range, its hardiness is likely to vary somewhat according to where the spore was collected.  One nursery in Germany has rated it to 7°F, and although I am not quite that optomistic, one has been thriving in Edinburgh, Scotland for several years now.  I think it may be an excellent prospect for Britain and the Pacific Northwest, as well as relatively arid or hot temparate climates such as the southern United States.

All of these characteristics imply a general toughness and adaptability that other treeferns lack.  On the negative side, it is very slow-growing and takes many years before the trunk starts developing.  But mature specimens are magnificent and well worth the wait: the fronds may reach 8' or more, making up a very attractively spreading crown; and the trunk is usually 18 - 22" thick.