Types of Irises
Irises, also known as fleur-de-lis, come in an astounding number of different varieties, varying in size, colour and appearance. The Iris genus contains over 300 species, from large bearded irises to dwarf irises.
Rhizomes irises grow from thick roots in the ground, producing sword-like leaves. Most of the irises from this group are evergreen. Rhizome irises can be separated into 3 main types: bearded, beardless and crested.
Bearded irises get their name from the way the outer petals curl into ruffled "beards." These bearded irises can be subdivided into dwarf (less than 15 inches tall), intermediate (16-27 inches tall) and tall (28-28 inches tall) forms. A common bearded iris found in gardens is the bearded German iris (pictured, at right).
Bearded irises are popular with gardeners, as they are hardy, the easiest type of iris to grow and are low-maintenance. They are also drought and cold tolerant. They thrive in well-drained soil and a sunny location. Flowers come in a variety of colours including, blue, red, white, yellow and bi-colour. Most bearded irises flower in the spring. Many varieties will bloom a second time during the fall.
Beardless irises have smooth petals and the leaves are thinner, almost grass-like. They produce flowers in a variety of colours including, white, yellow, pink, purple and blue. These irises native to Asia are popular cut flowers.
Beardless irises tend to bloom after the bearded irises-in mid summer. Beardless irises can be planted at the end of summer to early fall, depending on your climate. For the best performance, they need a sunny location and moist, acidic soil, preferably with added hummus or compost. The most commonly grown beardless varieties are the Siberian, Louisiana and the Japanese iris (pictured, at right).
The Crested Iris is a shade-loving dwarf variety, growing to be about 6-8 inches tall. Besides its petite size, the dwarf crested iris can be identified by its characteristic yellow or white cocks-comb-like crest in the centre of their outer petals (the falls). Crested irises come in shades of blue and purple.
Gardeners love to grow these irises; they are easy to grow and are low maintenance. Blooming prolifically in the early spring, they would be ideal as groundcovers or for use in rock gardens. They do well in woodland climates, especially under trees, with moist, well-drained soil. A commonly grown species is the Iris Cristata.
Photo credit: rodsguide.com
Like the name implies, these irises grow from bulbs, just like tulips! Bulbous irises are smaller than rhizome irises. Bulbous irises are native to Turkey and bloom in early spring. Popular varieties include: the Dutch (pictured, at left), English and Spanish irises. Bulbous irises are often used by florists as cut flowers.
They are distinguish by their small richly-coloured, puple-blue and yellow flowers. Interestingly, these irises lose their leaves after flowering. Compared to the other irises, the bulbous iris can be difficult to grow. They are planted in the fall and stay in dormancy over the summer. They prefer climates with hot, dry summers and mild winters. Only a few species are adapted to grow in North America.