Tuesday, 31 December 2013

Once thrilled by a Madeiran squill, I now have a geranium in the cranium


This time last year I was in London, contemplating a trip to the island of Madeira. Unfortunately it was a trip I never took. Back then I was excited about a squill, a lovely word conjuring up Dickensian rogues or perhaps a (s)pouting marine creature.

This time my Madeiran target has more familiar and mundane name, the geranium.


We call lots of things geranium but only some of them are botanically in the genus Geranium. Quite a few are Pelargonium, a genus segregated from Geranium after the many of the more common species were introduced into cultivation in the eighteenth century.

My featured plant today is a fair dinkum Geranium, but bigger than we are used to in Australia. Our native species are mostly of the creeping and scrambling kind, as I think are most around the world (the shrubby geranium we grow in our gardens is a Pelargonium).


Geranium maderense reaches more than a metre tall and about that wide. In nature it grows in the shade of laurel forest on the island of Madeira, about 600 kilometres off the west coast of northern Africa. In Australia, I noticed it recently in the beautiful Diggers Club garden at Heronswood, which reminded me that I'd seen a great specimen in the glasshouse of the Royal Horticultural Society's premier garden at Wisley while in the UK. (My pictures are from both locations.)

The laurel forests of Madeira are greatly reduced these days due to land clearing for agriculture. The remnants are now protected but there are less than 50 mature plants of Geranium maderense thought to exist at any one time. The species has been assessed as Critically Endangered by the International Union for Conservation of Nature and is included in its Red List of the world's rarest and most threatened plants and animals.

Thankfully (for the species at least) it grows well and attractively in gardens. It lasts a couple of years but produces plenty of seed - as yet I haven't read anything about it becoming weedy outside gardens.


It's easy to grow although I haven't seen it much around Melbourne. The robust leaf stalks with a distinctive swelling at their base are best kept even when the leaf they support dies. They will help support the often top-heavy plant. And like most geraniums (Geranium or Pelargonium) it tolerates drought, reputedly surviving months without water. So the best thing you can do is to not do anything much, and it will thrive.

Happy New Year!

Notes: I've sourced quite a bit of my information from a lovely fact sheet on Geranium maderense produced by the University of California Davis Botanical Conservatory. There is similar species from Madeira, Geranium palmatum, and the differences are outline in this post by The Frustrated Gardener.

2 comments:

Anonymous said...

Hi Tim--

Always enjoy your posts, from wherever they emanate.

I think, though, that you mean UC Davis, not David.

Best wishes for the new year from Ithaca, NY.

Tim Entwisle said...

Quite true - Davis not David (now fixed). Thanks for the correction, and for the feedback! Have a great New Year...