Date posted: 09 March 2018
In late February we received some very cool news all the way from Royal Botanic Garden Edinburgh (RBGE) in Scotland.
"@BotGardensSA you sent us seed of Doryanthes palmeri in 1957," a tweet from RBGE indoor horticulturist Simon Allan (@fondoffronds) began.
"... just wanted to let you know it's flowering!"
Intrigued, we reached out to Simon to find out just how this vulnerable monocot endemic to north-east New South Wales and south-east Queensland found its way across the globe.
Even more incredibly, we wanted to know how he managed to get it to bloom in a part of the world where the average daily maximum temperature right now is a frosty 7 degrees celsius!
An email from Simon, 24 February 2018
We recieved a packet of seed from Adelaide Botanic Garden in November 1957, and it was given our accession number 19570488 ( the first four digits are the year and the last four are the chronological order it arrived in our collection that year).
From these seeds several plants were propagated, and planted out into our glasshouses. One of those flowered in April 1985, after which that plant died.
The plant I have growing now [pictured, right] in our Temperate Palmhouse is from that original batch of seeds. It has been in the current postion since 2004 when the palmhouse was last refurbished and planted up.
I can't say for sure what the catalyst was for the plant to begin to come into flower. Although one day last summer I went to a meeting and forgot I'd left the hose running on the Doryanthes... as a result it was drowned for about six hours! I first noticed the shoot, or scape to be more accurate, in July of last year. It grew steadily until about October, when the light levels fell away for our winter.
The scape had attained a height of around four-and-a-half metres, and the individual buds a height of maybe 20 centimetres.
It then sat dormant and did nothing through the darkest part of winter. This winter has been unusually cold. Colder than we've had for maybe 10 years.
Anyway, it is still cold - we had a ground frost this morning - but the light comes back to us by around 7 minutes a day. In case that doesn't mean much to you, consider the fact we are at 56 degrees North. This is a higher latitude than Moscow, or Churchill in Alaska.
So the light has changed and now the plant is on the move again. I was relieved the plant decided to wait it out, rather than abort the flower spike. The buds are fattening and swelling day by day, and I expect the flowering to last several weeks, maybe months.
In the UK I know that Kew has some Doryanthes, with the last one flowering in 2015. Tresco Abbey Gardens on the Scilly Isles has had one flowering outdoors fairly recently, and as far as I'm aware only one other garden in the UK is growing it - Bishops Garden in Norfolk.
About Doryanthes palmeri
Doryanthes palmeri, commonly known as giant spear lily, is endemic to north-east New South Wales and south-east Queensland, and it grows in a rosette with leaves up to three metres long.
It gets its common name from the flowers that appear on a stalk that can reach up to five metres in height, and the species is considered vulnerable because it's found in so few areas in Australia.
We have 12 plants at Adelaide Botanic Garden (two at Mount Lofty and one at Wittunga), most notably surrounding the Santos Museum of Economic Botany, where visitors can marvel at its flowers in spring.
It can take more than 13 years for the plants to flower, and each rosette will only flower once in its lifetime (although the plant is then able to produce more rosettes).
Doryanthes palmeri has been used as a food source for Aboriginal Australians, whether via roasting its flower spikes or mashing the roots into a pulp to make cakes.
Learn more about these fascinating plants at the Australian National Botanic Gardens website.