There are over 250 species of Irises, which are found throughout the temperate and sub-temperate regions of the northern hemisphere. They range in height from 40 cm to 1.8m tall, with erect sword like leaves and tall flower spikes that appear in spring. Iris plants are separated into two main groups, those which grow from bulbs from drier regions and those which grow from rhizomes which prefer wetter conditions

All parts of the Iris plant are poisonous, though if treated properly can be used medicinally. The flower if chewed will burn or numb the mouth and if swallowed will induce vomiting and diarrhoea. Orris root, the rhizome from Iris germanica and Iris pallida is used to flavour some brands of gin.

Five species which are native to the south eastern region of North America are known as Louisiana Iris. The Louisiana Iris is of particular interest for South-East Queensland, as it grows well in our region and is quite hardy and will survive in clay, silty or sandy soils. They prefer full sun and love acidic, compost rich soils. Prepare the bed several weeks before planting for the best results. Divide rhizomes and plant out in late summer or early autumn. Place in a shallow hole with any green shoots facing up. Cover with no more than 20mm of soil followed by a layer of mulch.

Louisiana Iris’s also love their water. Water well when first planted and supply young plants with a weekly drenching. To reduce the need for ongoing watering, plant them in areas which are generally wetter than the rest of the garden. Small gullies where the driveway drains off, or even the overflow from your water tank will provide them with extra water. They will happily reside in the bog area at the edge of a pond as long as the rhizome is sitting at the surface of the water.

Feed with an Azelea/Camellia fertiliser at the beginning of autumn and the end of winter, just as the flower spike appears, heralding the warmer weather of spring.