Your iris book is right. 6" would, for beardeds, promote rot and death.

The Dutch iris may need winter protection in your zone??
Do any local gardens have them year round in the ground?

4" deep for the bulbous Dutch irises. Level with or slightly below (no more than 1/2") the soil surface for the beardeds.

Laurie

Dear jrdpa: One useful image that someone passed on to me for tall bearded irises: think of the rhizome as a duck on water. A small part of the duck is below the water but most of it is above the surface. The rhizome should be planted the same way! About a third below the surface and 2/3 above. Hope this is helpful!

Shapiro, that is a wonderful image! I hope you don't mind if I use it in the future. I do plant mine a bit deeper than a duck, though. More like loon depth, so the tops of the rhizomes are a little closer to level with the surface of the soil, but so they still have their backs exposed.

This is hilarious - I've been called a loon before because of my irises, but now I REALLY have a way to make the connection - I plant irises like a loon!

Diana

Well, I posted this to a response on the local paper's Gardening Forum and the administrator / garden writer seems to think it was right. He didn't answer about the hurt/rot though. I guess I'll keep my fingers crossed all winter now!

It seems like one page I came across in an old iris book said to bury bulbous irises and have the rhizome irises sticking out. My Dutch Iris were bulbs and my Bearded had rhizomes. I've never had Dutch Iris before so that surprised me. Would having the top of the rhizomes sticking out with the snow around here hurt/rot them? I went ahead and dug the 4" hole, but with all the roots the rhizomes had on them it pretty much filled the hole anyhow so it's sitting close to the surface really. I just planted the Dutch ones at the bottom of the hole since they didn't have any roots and that is what the Breck's label said. I'd hate to have all 31 of my irises not come up for some reason.

iris_gal, I have no clue if any of them have them year round. I'm in Pittsburgh, PA btw. I've been to three nurseries near my house and two of them don't really have anything planted outside. One is at a hardware store and is empty already for the year. I couldn't even find cheap long pots (troughs I call 'em) to plant my begonias in so I just stored them.

The second one is an actual nursery and is somewhat small compared to what I'm use to at home. They are all cement/asphalt outside and everything is potted. They close for the winter season as well I think. They haven't yet this year. I forget when they do. It seems every time I've tried to ask a question there I get someone who doesn't know squat.

The third one I've only been to once and wasn't all that impressed with. Maybe if I go during the regular season instead of the end of the season in search of vermiculite (sp?) for my Dahlia and Begonia tubers. All they had were pumpkins and mums and a few herbs really.

Oh and one little discount place near the house where we bought cedar. I got my Verbena there since they were so cheap. They really aren't a nursery, they just have a few things outside their main building. Their cedar was 3 for $10 though!

I really miss the nursery at home! They were so friendly!! They'd walk around and ask if you needed help and actually knew about everything!

I'm in a wet, big-tempurature-swings area. My Tall Beardeds do very well if 1/2 to 2/3 of the rhizome is above ground, somewhere between duck and loon depth. Any deeper and they rot, guaranteed. They like snow and ice on the rhizome just fine. There are a few varieties that won't overwinter here (they tend to be broken-colored iris, like Bewilderbeast or any of the Gnu varietes, which were bred in South Africa), but the vast majority do just fine.

Can't grow Dutch iris here, too cold. I think they are a zone 6 plant, so jrdpa, yours should do fine. And yes, they should be well buried. You can't treat Dutch iris and Tall Bearded iris the same way and expect success.

Good luck!
Jeanne

I've never grown any Irises where there is snow. This is my first attempt outside of Texas. Whenever we got snow at home it was rather light and wasn't even good enough for snowballs most of the time. It was gone the same day or the next day usually.

We just bought our first house this year so everything else I've done has been spring/summer pots up until now. I wish I could do plants indoors, but am afraid to with my kitties.

to jeanne in idaho,
I'm sorry, but bewilderbeast & the gnu varities were not bred in africa. they are the hybrid iris of brad & kathy kasperek. they live in northern utah. you can find his beautiful iris at zebragardens.com. they just like using african sounding names because they seem to fit his broken color iris better. the kasperek iris are my absolute favorites. I've planted quite a few of them in my yard. it's so hard not to plant them all. I don't know where you got the idea that they were bred in africa, but, that's not true.