Sunday, 2 January 2011

The portable glasshouse


In 1833, transporting living plants from England to Australia, was more difficult than transporting people.

The colony needed crops and vegetables, and seeds weren’t always suitable. On the reverse trip, the mother country was also keen to be living specimens of the newly discovered flora, for display and for economic use.

There was sea spray on deck, no light in the cabins below, little fresh water and rarely a trained horticulturalist on board.

A few years back retired Professor of Landscape Architecture at University of NSW, Richard Clough, documented the critical voyage that proved there was a way to keep a plant alive for more than 100 days at sea.

Dr Nathaniel Bagshaw Ward was known for his studies of growing plants in glass containers, particularly so that delicate plants could be grow in the polluted atmospheres of cities like his own, London.

His big discovery was what we now call the Wardian Case, and its use on ships making the longest voyages possible at the time, to Australia and back.

The case was essentially a mini-glasshouse, but sealed to stop the loss of water and gases. What we would now call a Terrarium. Plants produce oxygen and carbon-dioxide and with the right mix of plant material, air and water, can survive for extended periods without any extra care or attention.

The crucial test voyage was from London to New Holland. Leaving London in July 1833, the schooner Persian arrived in Sydney (via Hobart) on New Year’s Day 1834. After half a year at sea the plants in two Wardian Cases were landed at the botanic gardens, alive and well.

The acting superintendent at the time, John McLean (the boss, Richard Cunningham, had ‘gone to New Zealand botanising’), repropagated the plants and they all seemed to survive. McLean then restocked the cases with new plants for the return voyage.

From summer in Australia, through minus six degrees at Cape Horn (where a foot of snow fell on the deck, and the cases) and a sizzling 49 degrees at the Equator, the plants arrived in London in great condition. Seeds of our local Black Wattle (Callicoma serrata) had germinated en route, all without being watered.

The record keeping wasn’t great and we don’t know what other plants travelled in these two trips, except that a coral fern, Gleichenia microphylla, was successfully introduced into a glasshouse in England, a plant previously only know from dried specimens such as those collected by Banks and Solander in 1770.

Image: Modern day Wardian cases from wardiancase.com. *This posting is from the Radio Archives (January 2008).

3 comments:

Jim said...

Quaint images but this is what I thought a real Wardian case looked like. ;)

Tim Entwisle said...

Very true. We have a nice (olde worlde) Wardian Case we use for displays in the National Herbarium of NSW but I couldn't find a picture of it in my haste to post.
Tim

drey said...

Do you know where to get some glasshouses/wardians on stands in Australia? :)