Iris grow from tubers, the top of them is exposed above the soil for most varieties (or they rot). They typically will spread very well, so well I can't imagine taking the time to plant them from seed. And believe me, I usually plant any seeds I can get my hands on :)
I have had many different kinds for many years and I can always divide off tubers to share.
If you are buying them at a local nursery, be sure to check the zone hardiness on the package. I've noticed my local nursery's/home garden centers carrying varieties that are not hardy to my zone.

Hi steviewonder,

Welcome to The Iris Forum!

I think I know what the answer will be but I just can't bring myself to spend the money on the bulbs before getting an answer.
Chances are that one rhizome planted this year, will reward you with a stalk of beautiful blooms next year. Then the year after that, you will likely have 2 or 3 or maybe even more bloom stalks with several blooms on each one. Some are more prolific and multiply faster than others.

If you are not particularly wanting or needing named varieties, I would be glad to send you some NO ID ones for the cost of actual postage.

I just got the links set up on my trade page, so you can see what all I have available. If interested, please set up your Member Page email link, and then drop me an email. I won't be digging until mid to late July here in my zone.

See addressing newbie and newer member issues for instructions on your email link set up.

Sue...an enabler

Steviewonder,
Iris do well here in CO. Here is an example from my garden. We have to treat them just a little different than other climates due to our arid conditions. See my post to the thread "rescued iris/now what?"

This clump was a few rhizomes planted just 2 seasons ago:

LOL, someone gave me a bunch of this one and now I have 8 or 10 clumps like this. I'm finding new homes for them myself this year!

I just purchased all the stock from an iris & daylily display garden and hope to be selling iris commercially soon.

There are several very well known and quality commercial iris gardens in CO. What part of the state are you in? I can recommend one close to you.

Wow- you guys could be as nice as the people over at the Rocky Mountain Gardening forum.

I was thinking of visiting the Iris 4 U place, but I'm open to supporting other local gardeners' businesses. Also I wouldn't mind helping some of you with your 'weeding'. Right now I have veggies planted in the space where the irises would go so I'm looking at late fall or next year-- no rush.

I have my eye on the varieties 'Repartee' or 'Secret Service'. Anyone familiar with them?
Steviewonder

Iris 4U is a great place! You can wander around in the irises and take pictures and sniff if you want. It's nice to go pick out the iris and place your order right then.

In addition to Iris4U, there are:

C&T Iris Patch in Eaton- small but worth a visit
Long's in Boulder-Cathy is a delight. She sells for some of the local hybridizers.
Iris Colorado in Littleton- Lowell is a well known hybridizer in the state.

and a bunch of other, mostly smaller gardens too. Take a look at the AIS Region 20 sources webpage.

If I manage to get mine up & running I'll be near Fort Collins.

Here is a link that might be useful: AIS reg 20 source list