I believe "German iris" is the original name for bearded irises. The germans are not as tall as some of the new hybrid ones. If you do a google search for bearded iris, you should come up with a large number of iris dealers. I really like to order from ordinary citizens who grow in their own yards. They are often collectors and have more colors available than nearly anywhere. I have ordered iris from Select Seeds (they carry very old varieties) and also from E-bay sellers with good luck.

I'm in zone 7 Maryland, for me Siberians start blooming the middle of May, a week to two weeks earlier than the Japanese Iris. The foliage of Japanese iris is overall more subtantial than that of Siberians. The leaf is wider and thicker, and has a fat, rigid mid-rib that keeps it from being floppy. It also stays a nice medium green the whole season (not as dark a green as Siberians). If your Siberian foliage held up well for you, there should be no problem with the Japanese. I have actually left the foliage on the whole winter some years and it was a quite attractive gray-brown, standing tall until I cut it down in February or March. They (at least my Japanese iris) set a lot of seed, and the pods are also attractive. Letting them go to seed hasn't seemed to affect the amount of bloom I get year to year. Sometimes I deadhead, sometimes I don't. But, unless you are particularly interested in seeing the results of genetic recombination, make sure to remove the seed pods before they start to split open - three or four years ago I didn't and I'm still getting seedlings all over the place. One of the seedlings was actually quite lovely (I somehow missed it weeding, and it got to blooming size), having gotten a deep purple color and flat, round form from one parent and a stripe/stippling pattern from another, so I kept it; the rest have gone to the compost pile... - Steve

Flower size is largest on TBs. Supreme Sultan has been touted as the largest TB flower but new cultivars might have surpassed that, so you see there are variations within a class. IBs are like the slightly smaller flowered TBs but must be a shorter height to qualify (bloom size does not count). MTBs definately have smaller blooms. The dwarfs of course are the smallest. (Many of Blyth's gorgeous TB intros have smaller blooms ~ some breeders concentrate on size, others color pattern, etc.) Diseases that affect bearded iris affect all classes. The only one scary pest to me is the iris borer. We don't have it in the west yet. Do a search to read about peoples' experiences and "cures". The occasional pest mine have is scale in summer on old leaves. I run my fingernail along the leaf to remove it or cut off the portion (seldom spray). And some years iris leaf spot appears. It's disfiguring but that's all. Spraying with a fungicide prevents it. Someone else will have to give you the run-down on Siberian diseases/pests.

All bearded iris grow foliage in a fan shape from a rhizome. Check the FAQ for reasons why bloom is less. Don't fertilize with a high nitrogen fertilizer. It will promote leafy growth.