The Goanna's Feature Page On
The Sturts Desert Pea
Close up of the Sturt's Desert Pea.
Firstly some credits.. Photo's of the Sturt Desert Pea, and following Information on this my favorite Australian Native Plant from:
Courtesy of the Flinders University, Adelaide, South Australia.
Thanks to Dr. Greg Kirby and Dan Smith of Flinders University, Adelaide.
Info and pics: Australian National Botanical Gardens, Canberra and
Info and pics: The Society for Growing Australian native Plants.
Many thanks to Mr. Paul Dear,
Former Environmental Officer for the Roxby Downs Council in providing much inspiration for me to complete these pages.
Welcome to my feature page on the magnificently beautiful Sturt Desert Pea, A uniquely Australian plant.
Details, History, Legends and Propagation of the Sturt Desert Pea
Sturt's Desert Pea, Swainsona formosa, was adopted as the floral
emblem of South Australia on 23 November 1961, using the name Clianthus
formosus.
 The Legend..
The story as I understand it...
An Aboriginal tribe where camped in the desert.
A young Aboriginal woman watched as her man went out hunting.
She waited for his return but he was gone a long time.
The rest of the tribe decided they would move camp, the young woman refused to go stating she would wait for her man to return. They would then follow and rejoin the tribe.
As the tribe left they turned and could see in the distance, the young woman dressed in a red cloak, still sitting patiently waiting for her man.
Neither the young woman, nor her man were ever seen again.
However the next year as the tribe wandered, they came again on the campsite where they had left the young woman, and found exactly where they had left her a beautiful red flower with a black boss in her place.
The Sturt's Desert Pea
Recent History
This species, a member of the pea family, Fabaceae, is confined to Australia,
where it occurs in all mainland States except Victoria. The original collection
was made in 1699 by William Dampier on Rosemary Island in the Dampier Archipelago
where he collected a specimen from:
"a creeping vine that runs along the ground ... and the blossom
like a bean blossom, but much larger and of a deep red colour looking very
beautiful".
This specimen is now housed in the Sherardian Herbarium, Oxford. The
species was for many years included in the genus Clianthus now thought
to be confined to New Zealand.
Captain Charles Sturt (1795-1869) noted the occurrence of Swainsona
formosa in 1844 while exploring between Adelaide and central Australia,
and the common name, Sturt's Desert Pea, commemorates a notable explorer
of inland Australia, as well as indicating the plant's habitat and family.
Sturt's journal, Narrative of an Expedition into Central Australia, refers
several times to the beauty of the desert pea in flower and the harsh nature
of its habitat, and notes that beyond the Darling River:
"we saw that beautiful flower the Clianthus formosa [sic] in splendid
blossom on the plains. It was growing amid barrenness and decay, but its
long runners were covered with flowers that gave a crimson tint to the
ground".
The genus name Swainsona honours Isaac Swainson who maintained
a private botanic garden at Twickenham near London about the year 1789.
The specific name formosa is Latin for 'beautiful'. The original
author of the species was the Scottish botanist, George Don (1798-1856).
About the Sturt Pea
In its natural habitat Sturt's Desert Pea is a perennial plant with
silky grey-green pinnate foliage arising from prostrate stems. The leaves
and stems are covered with downy hairs. The flowers are about 9 cm long
and arranged in clusters of six to eight on short, thick, erect stalks.
The petals are usually blood red or scarlet with a glossy black swelling
or 'boss' at the base of the uppermost petal, the standard. The wings are located one on either side of the keel.
The keel is a hollow tube petal that contains the stamens and pollen,
then eventually the developing seeds.
Culinary Hint: The Keel can contain a small amount of sweet sap that can be sucked out to your taste buds delight.. Caution.. Beware of
caterpillar grubs. Check first before taking the sap or you may find your desert has a little more "body" than intended!!
Other colour forms range from white to deep pink, either with or without a black boss,
and rarely a bicoloured form, in which the standard is scarlet and the
other petals, the wings and keel, are white tipped and edged with scarlet.
The fruit is a legume about 5 cm long which splits at maturity releasing
several flat kidney-shaped seeds.
Drawing with labelled portions of the flower
The Future of the Sturt's Desert Pea
Dr. Kirby is a researcher at Flinders University in Adelaide S.A.
He is developing several features that will make the Desert Pea a
commercial proposition in the future.
These include longer stalks, and resistance to "Wilt Disease" giving longer "Shelf Life" of
the actual flower, making the pea more suitable for flower arrangements.
Also he is working on new colours and varieties such as multiple clusters of flowers on the one stem,
all White Peas (albino), and all Red Peas, and other variations.
See Sturt Pea Variations
My favourite though is still the wild red and black.
Clear photo of the general growth arrangement of the Sturt's Desert Pea.
Sturt's Desert Pea occurs in arid woodlands
and on open plains, (see map opposite) often as an ephemeral
following heavy rain. It is able to withstand the marked extremes of temperature
experienced in inland deserts, and light frosts are tolerated by established
plants.
Sturt's Desert Pea is protected in South Australia. The flowers and
plants must not be collected on private land without the written consent
of the owner. Collection on Crown land is illegal without a permit.
Swainsona formosa was introduced to England in 1855. It proved
difficult to grow on its own roots, but grafted on to Colutea arborescens,
Bladder Senna, it produced an admirable plant for hanging baskets.
Tissue culture is also used to propagate Sturt's Desert Pea. Small pieces
of stem tissue are grown on a nutrient medium under sterile laboratory
conditions. This method produces large numbers of identical plants from
a small amount of parent tissue and is a means of maintaining unusual colour
forms.
Sturt's Desert Pea was depicted on the 20 cent stamp
designed by Dorothy Thornhill as part of a set of six stamps issued on
10 July 1968, featuring floral emblems of the Australian States. The South
Australian emblem was repeated on the 7 cent
and 10 cent stamps, two of a set of six stamps issued on 1 October 1971
and 15 January 1975 respectively.
See Sturt Pea Stamps
The distinctive shape of Sturt's Desert Pea makes it ideal for use on
insignia, and on decorative items where it is readily identified either
in realistic or stylised form. The armorial bearings of South Australia
include two crossed branches of wattle at the base of the shield. These
bearings, which were granted in 1936, the Centenary Year, do not include
the floral or faunal emblems of the State.
A potted Desert Pea.
Getting into Cultivation!
In cultivation the desert pea was regarded as difficult, (though it really isn't if you know how!!) and few people attempted to grow it.
It is treated as an annual although it is, to some extent, a perennial if maintained correctly.
However, if the soil is deep and well drained in a sunny and, in particular, a protected position, it will have few problems. Watering regularly and with a dose of "Thrive" or
similar occasionally,
will see your Desert Pea have a long colourful life.
Germination of Sturt's Desert Pea Seed Is Easy
Seed is widely available. There are about 150 small kidney shaped seeds
in one gram but small quantities are available in packets.
In early spring, prepare the pot in which you want to grow the plant to maturity.
A 10-litre size pot or hanging basket will be ideal. The potting mixture should be
equal parts of sand, loam and peat.
Before sowing the seed where it is to grow, it should be nicked in the back of
the seed coat with a knife to break nature's long-lasting protective layer.
Place several seeds, widely placed, close to the
surface and drench the pot with a litre of general-purpose fungicide.
Seedlings should emerge in a few days. The young seedling's root system is growing so fast
at this stage that transplanting would be a problem. One centimetre of shoot may
have 10 centimetres of root.
Good Tip : "Jiffy Pots" (a small organic compound disk 30mm D x 5mm H that when immersed in water swells up
to about 40mm high) are actually the ideal means of growing seedlings, and a week or two after germination,
the whole lot can be planted directly where required, with no disturbance of the root system at all!!
Growing Of Sturt's Pea Plants
Place the pot in a raised sunny position. In winter where frost can be expected,
the morning sun should be kept off the plant. The western side of a building would be suitable.
Desert Pea should be protected from slugs and snails. During summer, Red Spider may be a problem.
This is indicated by a mottled brownish look especially on the leaf underside.
The grub (caterpillar) of a small blue butterfly will sterilise a flower
by entering the Boss preventing pollination, and also by devouring the seeds
in the forming seed pods. These should be sprayed with an insecticide.
Fertilize with complete slow-release fertilizer at half recommended rate in spring and autumn.
When the tendrils get too long and ungainly they should be pruned back.
Notes on botanical terms:
o Boss - a rounded protrusion at the base of the standard on Swainsona formosa
o formosa - from Latin formosus = "beautiful"
o Keel - in a "pea" flower, the two fused petals enclosing the stamens
o Standard - the large upper petal of a "pea" flower
o Swainsona - after Isaac Swainson, (a scientist and plant collector)
o Wings - petals at either side of the keel
 A mature
Sturt's Desert Pea in the wild.
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