Having gone many years without purchasing modern TBs, the observations I'm noting now, a year after placing a couple of vendor orders, are new to me. I'm curious if this is the norm for the rest of you as well...

Out of about 50 I planted last year from Mid America and Schreiner's, I would estimate about 40% of them bloomed this spring. Those that did not bloom are now notably larger plants than those that did bloom. Is this typical?

This has me considering other perennials that sources recommend removing flowering stalks the first year to conserve energy and put that energy into the root system. I find that very difficult, but may possibly be able to bring myself to do it. I have never heard of any iris growers doing that- have any of you heard of growers practicing this? Would it help?

I'd say that was in the "average" range, Neal....I usually have about half that don't bloom the next year. And, I'm sure the "non-bloomers are larger , now.......they didn't spend the energy to bloom....just made growth, instead
As to removing the stalks.......I've never done it....seeing the bloom is why I have them , so it makes no sense (to me) to "give away" THIS years bloom, for the possibility of MORE bloom, next year. I suppose if the plant's survival was doubtful, I might cut the stalk , but , generally, if it is that "sick", it won't throw a stalk ,anyhow.

Arlyn pretty much said what I would have.. Cut a stalk I've waited a year (or more) for? I wouldn't be able to do it

I have found the ones that haven't bloomed didn't increase as much as those that have bloomed. The non blooming ones spent the year fattening up.

Remember; the rhizome only blooms once. The making of increases is a timing thing (I think-my uneducated guess)and I am not sure that removing the stalk will signal the plant to start putting all its energy in increases. I would guess my average of the last 5 years at better than 50% (I would hazard a 60/40 ratio). I have had some bloom in the 3rd year, so some are just more finicky about being moved about.

I've had a puzzling experience with several irises - they will "knock themselves out" with vigorous
blooming, then they just poop out. First year Earl of Essex wouldn't quit last season, with several flowerings, but now he's kind of
died back and has just one small increase. Should I fertilize him, give him extra water, or just talk sweetly to him?

I think some vendors rely on giving the rhizomes more nitrogen to produce more leaves and less blooms if they need an iris to multiply for sales stock.
If a healthy rhizome, that has been taken care of, and given proper nutrients and water throughout the previous year, is sold, the buyer can expect a higher percentage of bloom than a rhizome that has been out of the ground for an extended period of time. Whether this is due to the vendor digging and packaging them a week later, shipping issues occurring or perhaps not planted immediately by the receiver does not matter. The rhizome (and I may be wrong, I was once before) is not a bulb but an underground stem. It does survive if not planted immediately but it is not like a spring flowering bulb that stores bloom energy and goes completely dormant. When it is out of the ground and has used a lot of the moisture in the rhizome to survive and the roots and leaves begin to dry up it has used up its bloom energy for the following spring. Some irises are finicky but I think more are blamed when perhaps their needs were not met. IMHO

Earl of Essex is a re-bloomer, so it needs more TLC after the Spring bloom than other "regular" irises. So give it a boost, but this should have been done in June. Give only a little. (since you are in N CA it may be too late for this year to boost it much, but every bit helps. A boost now may get you a bloom in the Spring.)

Nearly always when a new plant doesn't bloom for me, it increases at a much better rate then one that has bloomed. However, that's not an absolute, but a generalization. I've also learned that if I make a seed pod on a bloom, that it seems to increase even less. I used Ginger Ice really heavy this year (5 pods) and it just has a few tiny increases, and I doubt if it will bloom next year. The percent of bloom from new plants I think, may be greater in areas with a longer growing season. Up here, it's often 40% or less for newly planted irises. Of course with the rot I had this year, it was probably less then that. Last year I had several new starts that I planted in June, and I had a better bloom outcome from them then those planted in July or later. There are so many variables that it's hard to generalize this hypothesis too much.

I was under the impression that the first year bloom of a newly planted iris was formed in the previous location of origin so whatever happened there is an unknown in most cases. The general rule I think is that about 50% will bloom the first year but that is from the place of origin. Many of mine bloom the first year but not the subsequent year. It is hard to figure out what triggers increase and bloom volume other than the care you give, the unpredictable nature of the weather and the individuality of the cultivar. I think.......

Henhouse said:Arlyn pretty much said what I would have.. Cut a stalk I've waited a year (or more) for? I wouldn't be able to do it

Yikes, I have waited through the long Idaho winter for those blooms. A few weeks ago I might have almost said I would rather cut off my hand first, but after being in a sling and shoulder brace for the past six weeks, that ideas is too appalling. However, I do not think I COULD CUT A BLOOM STALK!!! Not when every one is marked in my mind and daily checked for imminent blooming. Open, open open!

I have had better than 50% first year bloom, I am averaging about 70%. That said, I have a much smaller amount that bloom again in their second year. Those that have been around a long time always bloom every year, but that has not been the case for the new ones **. Owyhee Desert may be a slow grower, but blooms every year. Coal Seams and Slew O' Gold are following that trend. But my other TB's? I haven't figured out the Magic to make them predictable bloomers.
** this does not apply to my dwarfs that really really like to bloom and do every year.

I order iris from Keppel, Ghio, and Mid-America and get a few from friends and a few at our Society Sale. I haven't kept records but I think I get at least 80% bloom the spring after planting

I planted a lot of iris in March/April. Today they are doing incredibly well and have grown extensively. I expect them to bloom next Spring. I agree with Tom - I think the longer growing
season has an effect on bloom. I planted iris rhizomes in March, April, May, and June. I expect
these iris to be blooming next Spring. All of my other rhizomes were potted up in July and planted out in the garden in August. Their root systems were extensive when it came time to
un-pot them and transplant them into the garden, I was amazed at their extensive root systems.

Sounds like stalk removal isn't a decision I should concern myself with- I'm sure if it were practiced and found helpful, at least some of you would have heard about it. Even with those perennials where it is recommended, I find it really challenging to make myself do it.

As much as I enjoy seeing blooms from new plants the first spring, I do prefer seeing irises bloom in clumps. The clumps most of the non bloomers have formed look really promising!

Some mentioned the timing of planting new rhizomes, and I too am seeing the best development among those that were planted early. Several from Suzanne and Bonnie were planted in May or June and look like they've been growing in their present spot all along- I would be surprised not to see blooms from those.

Everyone has already said what I would have said. I CAN'T cut a stalk I've been waiting a year or more to see...an iris or any other plant. MHO is, if it's going to perform, it will. Or not.

I think I had more to say but I'm just starting my 2nd cup of coffee and the brain isn't fully functional yet.

Totally agree with everyone else here -- I would never -- make that NEVER -- cut off a bloom stalk -- even if it did the rhizome any good. Which I doubt.

Once, quite some time ago (which is probably why I don't remember all the details ) I read an article ( I *think* it was by Chuck Chapman) concerning "how many leaves have to grow, before a rhizome developes a "blooming point" , and makes a stalk." It was the writers contention (and I think there were some pictures , to illustrate the "scars") that, by counting the "leaf scars" (those little "lines you see along the length of the rhizome) you could tell "when" the rhizome was likely to bloom. In other words....a rhizome has to grow "X" number of leaves, before it will ever bloom. So, does anybody else remember this article, or , have you ever heard this before ? I'd love to "revisit" the information. It may have been on Facebook, or, in an AIS bulletin....probably 4-5 years ago............thanks

I have heard from several iris growers that Immortality will re after nine new leaves. I don't think I have that one.... don't know why I don't it may re here. If I get it next year I am going to start keeping a leaf log.

Hmm, leaf counting I have never heard of this topic! I am interested in rebloom so please post about the outcome.