(Iris germanica cultivars)
Bearded Iris are identified by their often colourful, thick, bushy “beards” on the falls (lower petals).
Originally, most of these were native to central and southern Europe. It is important to know that each rhizome only flowers once. The plant survives by producing increases (babies).
Originally, most "Bearded" irises were native to central and southern Europe. They are identified by the often colourful, thick, bushy “beards” on the falls (lower petals). They are perennials which spread by rhizomes and it is an important fact to remember - each rhizome only flowers once - its job is to produce increases or babies so the plant can continue on. When they spread this way the daughter plants are identical to the mother. If they produce seed pods, the seeds will not be identical to the mother and each seed in the pod will be different. Some types of bearded iris are better suited to growing in pots then others, however they need extremely well drained soil and care must be taken not to over water as they can rot very easily, especially in summer.
TALL BEARDED IRIS
These stunning, plants (known as TBs) like slightly acid to alkaline well-drained soils, full sun, cool to cold winters and hot summers. They are extremely hardy and require only light watering throughout summer. They appreciate a slow release, low nitrogen fertiliser, or a balanced organic fertiliser. Do not place water-holding mulch directly on top of the rhizomes as they may rot.
They are best divided (every 2-4 years) soon after flowering (Nov-Dec) or late summer or autumn (Mar-May), but they will survive being moved almost any time. If you must move them in Jan-Feb, be careful not to over-water as it can induce rot. They are best grown where they get full summer sun however in very hot areas they may benefit from some afternoon shade.
Bearded irises should not be planted deeply. In most areas of Australia they are best with 1-2 cm of soil over the rhizome with the junction of the rhizome and leaves at the surface. In the Australian climate, allowing the rhizome to be exposed may cause scorch.
To be classed as a "tall" bearded iris their flower stalk must reach 70 cm (27 1/2 inches) and above.
MINIATURE TALL BEARDED IRIS
This class is distinguished by daintiness and delicacy. Height from 41 cm (16 inches) to 70 cm (27 1/2 inches). The blooms are smaller than on a BB and the stems are thin and wiry. An MTB clump looks like a cloud of butterflies. They are often called "Table Irises" because they are so well suited for arrangements. They are not commonly grown in Australia.
BORDER BEARDED IRIS
Border Beardeds (BBs) are essentially small versions of the TBs in the same height range and bloom size as the intermediates (41 cm to 70 cm), but blooming with the tall beardeds. The earliest BB were sometimes tall-bearded runts but good BBs should have a sense of proportion commensurate with their stature. Good BBs have round, ruffled petals that complement their small size.
INTERMEDIATE BEARDED IRIS (IB)
Intermediate Bearded stand from 41 cm (16 inches) to 70 cm (27 1/2 inches) high, with their bloom season overlapping the SBDs and the TBs. Although the IBs show their dwarf ancestry in early bloom season and very interesting color patterns, they are large enough that their individual stalks may be nicely branched, forming an elegant bouquet. Some varieties are nicest in clumps, where they present a large amount of colour (like the SDBs), while others are showiest in specimen plantings, where the stalks and individual blooms may be seen to best advantage.
Intermediate Bearded Irises are crosses between dwarf and tall bearded iris. They are often infertile. They require cooler conditions and a bit more watering than tall bearded iris.
STANDARD DWARF BEARDED IRIS
Standard Dwarf Bearded Iris (SDB) range in height from 20 cm (8 inches) to 41 cm (16 inches). They begin their bloom as the MDBs are ending, still quite early in the iris season. They are best displayed in clumps where they give the effect of a "cushion" of individual blooms. The colours are nearly unlimited since the SDBs show all the different "spot patterns" of the miniatures, as well as the plicatas and pinks seen in the TBs.
MINIATURE DWARF BEARDED IRIS
Miniature Dwarf Bearded (MDB) are the tiniest of bearded irises, with height of up to 20 cm (8 inches). They are also the earliest to bloom. They are most effective in rock gardens or planted in drifts where they make a "carpet of colour."
Hybrids have been produced from crossing the arils# with the more common bearded irises. These are called "Arilbreds" (AB), and are usually very easy to grow and still display the spectacular features of the arils. Most arilbreds are tall and have large blooms however many are under 70 cm (27 inches). They usually bloom earlier than the TBs, with the SDBs and the IBs.
# Pure aril irises originate from desert areas and are rarely grown in Australia.