Dracunculus vulgaris: Dragon Arum. (Andrew Broome, January 2002)
Dracunculus vulgaris Schott (1832) is a common plant in many parts of the Balkans, the Aegean Islands and southwest Turkey. It's also been found in Italy and Africa but these are generally accepted as being introduced colonies. It has been cultivated for many years for ornamental purposes but has never been a common plant in the nursery trade. Generally it seems to be one of those plants that people have and pass on to others but which never gains huge popularity outside of people with an interest in the unusual. It may be seen under the common name of 'Dragon Arum' as well as variants on the 'Voodoo Lily' theme.
There is one other species in the genus, Drac. caneriensis which comes from the Atlantic islands of Madeira, Gran Canaria, La Palma, and Tenerife. It is reported to have a different odour and is therefore probably pollinated by different insects. As far as I know, it's not available in New Zealand and neither are any of the Drac. Vulgaris variants (mostly different in 'flower' colour). Some people include the mono-typic Helicodiceros in with Dracunculus but generally, and for the purpose of this article, it will be excluded.
Dracunculus vulgaris is a tuberous perennial member of the Araceae family and the Aroideae sub-family. It's generally considered to be related to plants such as Arum and Eminium. The tubers are flat and disc shaped with a definite 'growing point' at the top from which roots and a stem will appear at the appropriate time. Tubers can get quite big, supporting a stem 2cm thick or so which appears in late winter as a green and white mottled spike, perhaps tinged with pink. Growth at this stage is rapid and the first multi-lobed leaves are usually apparent a couple of weeks later. These leaves are divided and may have the edges curled up. There are also sometimes white spots or streaks. During the spring several more leaves will grow opposite each other but further up the elongating stem and, in mature plants, generally a couple of years old and 60cm or more tall, this will culminate in a flower spike up to 45cm high. The word 'flower' is not technically accurate here as the parts you see are actually a modified leaf called a 'spathe' with a large central spike known as the 'spadix'. The spathe is a dark purple colour with a velvety appearance while the spadix is brownish-purple and often pitted.
Many of the aroids are pollinated by non-conventional insects (ie, not butterflies or bees) but rather by carrion or excrement feeders such as flies and some beetles. You can therefore probably imagine the odour that is emitted by the flower in order to attract potential pollinators. Drac. vulgaris is no exception and has a pretty potent and, to many, offensive odour once the flower is fully open. When grown outside, this is generally not too much of a problem except on the hottest and most wind-free days when things can tend to linger somewhat.
Not long after flowering the plant begins to re-adsorb nutrients from the leaves and stem and often by January it will be completely dormant. Large tubers freely send off smaller tubers and as such in several years you may end up with a large clump of several growing points. These tubers can be dug up and moved or distributed to other growers. Generally they'll pop up the following year but sometimes they'll skip a year, especially if they've been moved too close to breaking dormancy.
Drac. vulgaris can be grown in large pots or in the garden. They prefer free draining soils and won't like sitting with their tubers in very wet ground for long periods. I'm currently growing mine in large pots and once the plant has gone completely dormant I stop watering and put the pots under a tree or grapevine such that they receive the occasional drips of moisture but are kept pretty dry. They are pretty heavy feeders and during active growth will appreciate some fertiliser or fresh compost.
So, to finish, Dracunculus vulgaris, and indeed many of the other tuberous aroids, are not plants for everyone but they do have a place in the garden especially for those with an interest in the unusual. You can be sure that they'll attract attention and comments when people see them, especially when they're in flower.
Pictures of the plant and flower can be found at various places on the internet. A good place to start would be:
http://users.pandora.be/roger.van.loon/drac-vul.htm
although any good search engine (I use http://www.google.com) should be able to find many references.
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