At Ventnor Botanic Gardens in the Isle of Wight I. australe is one of those plants which has self sown itself all over the garden terraces and is one of the signature plants, alongside echium, puya and eucalyptus, of this cliffside garden.
I. australe is a deciduous shrub growing (in the Isle of Wight) 8-10ft tall with a flowing and arching habit. The leaves are dark green, lance shaped and up to 3in long with lighter green undersides. In May or June each growth spur produces one to five funnel or bell shaped deep blue, lavender or even white flowers which are an inch long. You can still see flowers on these plants in July and even August.
The reference books indicate that this plant is half hardy but we would recommend that you do not risk it outside except perhaps as a wonderful patio plant that comes back into the greenhouse in the autumn.
Young plants can be pinched back in spring to encourage bushier growth. Feed sparingly or risk too much new growth and too few flowers. At Ventnor we have seen plants growing in full shade but they are best grown in sun with some shading from the hottest sunlight.
Anything with blue or lavender tubular flowers is highly desirable but this plant will need fleece protection in a cool greenhouse. Cuttings are easy to root but do not expect seed in our climate conditions as these are plants from Bolivia and Argentina. Grow them with fuchsia species from these countries for best effect (eg F. boliviana)!
