Dicksonia antarctica

OLYMPUS DIGITAL CAMERAAs one of the most popular examples of this fascinating and fashionable group of plants, it is seen more and more available for sale. Appearing like a fern on top of a short trunk its slow rate of growth is reflected in its relatively high price. There is a lot of confusion over its hardiness with some saying it is only hardy in the mildest areas of the UK while others, including Kew, say its foliage is hardy down to -2°C but the plant itself is hardy down to -10°C. Part of this may be expectation as it is only found in the tropical regions of the southern hemisphere, but may also reflect the location a particular plant has been collected from as it is found at up to 1000m above sea level where plants would be expected to be more cold tolerant. With that in mind, and considering the cost of the plants it may be as well to adopt a cautious approach as frost below -10°C are not unknown in most parts of the UK and provide some frost protection. This is commonly achieved by wrapping the plants in horticultural fleece or straw secured with chicken wire.

Dicksonia antarctica

Dicksonia antarctica

Dicksonia Antarctica Labill. Thrives in cool damp situations: given time and the right conditions it can achieve a 3 metre trunk and 2.5 metre long fronds. To do well it needs plenty of water and given enough water it is quite tolerant of exposure to sun. As you might expect from its natural habitat it does best in a humus rich acid loam but it is quite capable of growing in most soils, even poorly drained ones. There slow rate of grow makes them very suitable a pot plants, which allows them to be moved indoors in cold weather, but they do resent being pot bound. The strange structure of the trunks means the top of a tree fern can be cut off and will regrow if being planted; but the lower potion will not as it is composed of dead material.

The extant species of tree ferns are a remnant of a far greater group which helped lay

Dicksonia antarctica trunk cross section

Dicksonia antarctica trunk cross section

down the coal seams mined today. They do not form a taxonomic group as such and the term only refers to any tree with a wood like trunk raising the fronds off the ground. In UK gardens Dicksonia Antarctica Labill.is the species most commonly found and as originally described by Jacques J.H. de Labillardière. M. Labillardière published his description in the second volume of his to volume Novae Hollandiae Plantarum Specimen, which was the first flora published of Australia (or New Holland as it was then known). The journey from Australia to the floras publication in 1806 was anything but straight forward. Labillardière was a naturalist attached to the expedition the French sent out to find what had happened to the expedition lead by Jean-François de Galaup, comte de Lapérouse. They failed to find the lost expedition but did explore parts of Australia, New Zealand and surrounding islands. While they were away The French Revolutionary wars were causing upheaval in Europe and on reaching Java the expeditions scientific collections were seized by the British. It was only by appealing through influential British contacts that he was able to secure their return and so publish their descriptions.

References:

Dicksonia trunk showing aboriginal carving

Dicksonia trunk showing aboriginal carving

http://www.kew.org/plants-fungi/Dicksonia-antarctica.htm

Encyclopaedia of Ferns by David L. Jones

Hardy Garden Plants (3rd Edition) by Graham Stuart Thomas

http://www.forestferns.co.uk/

‘The International Plant Names Index (2012). Published on the Internet http://www.ipni.org [accessed 24 June 2013]

Novae Hollandiae Plantarum Specimen by Jacques J.H. de Labillardière

Garden Myths: Number 4

You can get grass to grow well in the shade.

No you can’t. Grass will put up with a lot; how any plants will put up with being regularly cut down and walked all over? Like everything it has its limits and it is never happy in shade, needing full sun to do well. What about shade “tolerant” grass seed varieties you say? Yes, some grass is more tolerant of shade than others; but that’s not the same as happy in shade. If the shade is slight these are probably a good idea, but once you start to get under trees and the like you cannot expect them to be any better than any other grass.

Fatsia japonica

Fatsia japonica

Fatsia japonica

One of the classic garden plants for shade Fatsia japonica is much admired for its large, glossy, evergreen leaves and easy temperament. It grows happily in any reasonable garden soil and does particularly well in shade, though not so well in dry shade. It is also tolerant of a maritime garden though its large leaves will need some shelter from strong winds. The large fleshy leaves evoke the image of lush tropical rain forests but the plant is reliably hardy, though the result of crossing it with ivy produces the less hardy x Fatshedera lizei. Quickly forming a medium sized shrub with flowers borne on the end of the shoots. The flower buds and white flowers look a lot like a scaled up version of Ivy flowers, appearing in autumn. This late flowering means though the buds are reliably formed in the UK the flowers are often damaged by frost.

Fatsia japonica leaf

Fatsia japonica leaf

Known by a variety of common names including Japanese aralia, castor oil plant, fatsi, fig-leaf palm and glossy-leaved paper plant; F. japonica was originally described by Carl Peter Thunberg in 1780. This followed his trip to Japan where it grows wild and he named it Aralia japonica. It was re-named in 1854 by Joseph Decaisne and Jules Émile Planchon, two botanists working in France. They took it out of they genus Aralia and created the new genus Fatsia for it; so the name is now Fatsia japonica (Thunb.) Decne. & Planch.

In the wild Fatsia japonica is found from central Japan south along the Japanese islands almost to Taiwan and in South Korea. It is sometimes described as a monotypic genus, meaning that there is only one species init, but in fact there is at least two other species of Fatsia, Fatsia oligocarpella Koidz. and Fatsia polycarpa Hayata.

Fatsia japonica 'Variegata'

Fatsia japonica ‘Variegata’

It was introduced to western horticulture in 1838 and though the plain green Fatsia japonicais the one most often seen in gardens others are available and the variegated form Fatsia japonica ‘Variegata’ which has splashes of white on the leaves is worth looking out for.

 

Hydrangea aspera

 

Hydrangea aspera

Hydrangea aspera

The rough leaved Hydrangea is one of the less commonly grown examples of this important genus in our gardens, but makes an excellent addition to the garden. The large velvety leaves provide an attractive display all summer covering this medium sized bush. And come June and July this is topped with dark lilac “lacecap” flowers. As is typical of Hydrangeas Hydrangea aspera D.Don is easily grown and need a shady location, making it ideal in front of a north facing wall or fence, or in the shade from trees. It is a very variable species and some people have questioned its hardiness but I have seen it grown successfully all over the UK. That said it probably benefits from some protection, particularly from strong winds which would damage the leaves, though this protection could easily be provided by the fences around most gardens or by a woodland aspect.

Hydrangea aspera flower

Hydrangea aspera flower

An oriental species it is found growing wild in the Himalayas, West and central China,Taiwan and Myanmar (Burma). It was first described by the Scottish botanist David Don in his 1825 flora of Nepal, placing it in Linnaeus’s genus Hydrangea L. In gardens it is often represented by Hydrangea aspera D.Don ‘Macrophylla’ a sterile selection with large leaves and flowers.

The variability of Hydrangea aspera D.Don, probably due in part to its wide geographical distribution, has lead to a degree of confusion regarding the different subspecies, cultivars, etc. The RHS database lists about 38 different entries under Hydrangea aspera D.Don including several subspecies. I it is doubtful how many of these are valid as the International Plant Names Index (IPNI) does not recognise any valid subspecies of H. aspera,raising them to the level of species.

Hydrangea aspera foliage

Hydrangea aspera foliage