Patersonia is a genus in the Iridaceae family with most of the species endemic to Australia and a couple of other species from Borneo and New Guinea. Most species are evergreen with linear or sword-shaped leaves in fan-like groups. There are a couple of species from dry areas that are bulbous, but most are rhizomatous. The flowers are short lived, but many may be displayed during their flowering period.
Seeds (fresh or old) seem to germinate with difficulty. Dirk Wallace finds that treatment with smoked water or a top dressing of wood ash seems to help.
Patersonia occidentalis is a species that occurs mainly in coastal areas in Victoria, Tasmania, Western Australia and South Australia. This species grows both in sandy and clay loam soils and soils that are both well drained to poorly drained in semi-shade to full sun. It grows to 75 cm. tall and blooms spring into summer. It probably does best with year round water. The first two photos show plants finally blooming in a northern California garden in 2005 a long time after they were started from seed. Flowers only last part of a day, opening mid morning and closing later in the day. 2005 was a year with regular rainfall lasting much longer than it usually does and plants have not done as well in subsequent years. The last two photos were taken in Perth, Australia October 2007 at King’s Park. I assume they are this species, but the plants in this display were not named. Photos by Mary Sue Ittner.
Patersonia spp The photos below were taken by Mary Sue Ittner and Bob Rutemoeller in southwestern Australia in spring 2007. I’m not sure which species they are but I suspect most of them are either Patersonia occidentalis or Patersonia umbrosa as most of the other species that might be found where these pictures were taken are shorter plants. The first two pictures were taken near Walpole. The third picture was taken along a trail next to the Kalgan River near Albany. The last pictures were taken at William Bay National Park.
Patersonia umbrosa is a species from Western Australia with two varieties.
Patersonia umbrosa var. umbrosa grows in winter wet swamps in heathland and open forest in southwestern Western Australia It grows to .9 meters high and has blue to violet flowers to 7 cm across.
Patersonia umbrosa var. xanthina syn. Patersonia xanthina, grows in lateritic gravel, sand and clay in jarrah and karri forests in winter wet areas, swamps, and hillsides in southwestern Western Australia. It is a rhizomatous perennial that grows to .75 meters and has yellow flowers about 5-8 cm. across. Photos taken near Pemberton in Western Australia September 2007 by Mary Sue Ittner and Bob Rutemoeller.