Just in case you thought all irises were beautiful, I added the last photo which I thought was a pretty scary looking flower. The second to third last photos were taken last year at Meigetsuin gardens in Kamakura which is one of the most famous places in Japan to view irises right around the corner in June. Irises during this late season are called hanashoubu.
About Irises: There are about three hundred species, they grow just about anywhere even in the desert and only need sunlight. More info below from a great website Homepage for Irises: and also Japanese Irises
A gardener’s classification of irises
A biologist’s taxonomy is very helpful, but it doesn’t distinguish between kinds of irises the way gardeners do. A gardener might divide irises first into two groups: bulbous irises and rhyzomatous irises. The bulbous irises might then be divided into three parts: Dutch and English irises (genus Xiphium), Reticulata irises (genus Iridodictyum), and Junos (genus Juno). The rhyzomatous irises (genus Iris) could be divided into three major parts: beardless irises (subgenera Limniris and Xyridion), crested irises (subgenus Crossiris), and bearded irises (subgenus Iris).
Most of the irises that a gardener would grou would be in the beardless iris group or the bearded iris group. The beardless iris group is a very wide group; beardless irises usually won’t even crossbreed unless they’re closely related. The bearded iris group must be more closely interrelated since many will crossbreed with each other often producing fertile seedlings.
There are several groups of beardless irises recognized by gardeners. In fact, some gardeners are devoted to just one of these groups. Siberian irises (series Sibiricae) and Pacific Coast irises (series Californicae) are two such groups. Some of the Siberians will cross with the Californicas resulting in a hybrid group called Cal-Sibes. Unfortunatly, they’re nearly always infertile. Japanese irises are bred from a species in the series Laevigatae. Two other groups of beardless irises are the Louisiana irises (series Hexagonae) and the Spuria irises (series Spuriae). In Rodionenko’s classification, Spuria irises are placed in a different subgenus (Xyridon) from the other beardless iris mentioned here.
Bearded irises are the most popular irises. The `true’ bearded iris hybrids (section Iris) derive from a wide variety of species belonging to the series Pumilaie, mostly smaller irises, and the series Elatae, mostly larger irises. The American Iris Society classifies bearded irises into six groupings based on size: miniature dwarf, dwarf, intermediate, miniature tall, border, and tall. Another, more exotic, group of bearded irises are the Aril irises (section Hexapogon) which includes Oncos (subsection Oncocyclus) and Regelias (subsection Regelia). These interbreed with the true bearded iris to produce what are called Arilbred irises.