Iris bloom irregularity.

Can a sudden cold snap cause iris blooms to go "all wonky"?

By that I mean that the bloom fails to color properly and isn't completely formed as far as ruffled edges, fullness and so on.

I had this happen on some "yellow flag" as well as german beardeds.

Don't have a picture, but hope the description is a clue.

What causes this?

Robert.

I had a late freeze last year that caused the buds on many of my Tall beardeds to just dry and fall apart. Other iris and daylilies showed mal-formed and discolored blooms from the hot March and cold April.

If it is any consolation, my iris apparently put all their energy into the roots instead of blooming. I have HUGE clumps with hundreds of buds this year. I hope yours do the same.

We had late freezes followed by high 80's and then back to cold. Sounds like that is what happened to my iris.

I noticed that late blooms on the scape seemed to recover some of the color, but they were still undersized and weird-looking.

Plants are otherwise healthy.

Thanks.

Robert.

Robert,

What you are describing sounds like herbicide damage to me. Have you or any of your neighbors used RoundUp or similar in an area from which your irises could have caught some drift? If it is herbicide damage, your irises should bloom normally next year, assuming they don't get hit with herbicide again then.

Laurie

Laurie~

I think you've hit it!

I had used Round-up all around them and yes, they could have (and prolly did) get a whiff of it.

It's funny, because many of the first blooms were perfectly normal and later scapes had the "knarly" blooms and I wondered how the freeze would have caused the damage. Are Iris particularly sensitive to Round-up?

I'll make sure I spray more carefully next time. I think there was some wind that day........

Thanks.
Robert.

Yes, irises are quite sensitive to RoundUp. It won't kill them (although I suppose it might if the dose were high enough or the plant was already weakened or very small), but it will cause some pretty nasty bloom distortions. RoundUp is really not something you want touching your irises.

Laurie

I had many undersize or irregular bloom size on my garden newbies this year and Roundup wasn't involved but fluxing temps were rampant. Dry February, Hot March, Cold April, Wet May. What a mix up!

I have seen Roundup color changes one year when the neighbor had TrueChem lawn repair come into their yard to spray for Dandelions et al. Everything closest to the fence (6 feet away) was 1/2 white, 1/2 colored.

R.

Let this be a lesson to us all.

Robert.

Another thing I noticed, especially on the I. pseudacorus:

There were partially white leaflets on the scapes with the distorted blooms. I think there are some more coming along and I'll see if I can get a pic tomorrow, of the blooms if not the foliage as well.

Robert.

I had the misformed buds & stems last year with NO use of insecticides. Just good old Iowa weather. The first daylily scapes and foliage were ugly last year too.

There weren't any of the white leaves to be seen or photographed. I had already removed all of them.

The mis-shapen blooms, mostly *very* small ones now, are still coming on the yellow flag. "Cotton Lace" has one scape with un-ruffled blooms that are smaller than normal.

I can't do anything about it if it's caused by weather, but I'll be more careful with the chems.

Robert.

I think maybe this is where I want to ask my question. I have some Iris I bought from Schneiders so I think they are good stock but they are blooming sporadiacally. They are probably 3 years old and only one bloomed last year. This year more of the varieties have buds on them. I put them in a sort of a "hill" because my ground is so poor. Most of the rhizomes are exposed and I think that may be part of the problem. I top dressed them with compost for now but wonder if I should dig them up and replant them come July, which is the suggested time to replant. Another question is how to keep grass out of them. I am thinking of planting a ground cover such as sedum or creeping phlox with them and wonder if anyone has any experience with that. Thanks

synergy,

There are many causes for non-bloom in irises. I have written a FAQ concerning this problem that you can find here:

http://www.angelfire.com/mn3/shadowood/irisfaq.html

I can tell you from my own experience here in northern MN that it is not at all uncommon for irises purchased from the West Coast to take several years to shrink down and acclimate to my climate before they'll start blooming for me. Also, tall beardeds usually don't bloom every year in my short season climate. They simply don't have time to mature new rhizomes to blooming size in a single growing season up here, so they often only bloom once every 2-3 yrs. I generally get much more reliable, yearly bloom from the median irises than I do the talls.

Grass in the iris beds? Good luck! I'm waging war against quack grass right now. If you come up with a solution, please let me know!

Laurie

Laurie,
Thanks for sharing your experience with shrinking rhizomes. I was wondering about that. Mine are smaller and sometimes I feel bad about the size of them when trading/sharing. But they still blossom. This year I'm using some triple phosphate, about a tablespoon scattered around each plant/clump, to see if that will pump up the rhizomes a bit. Luckily, we have dependable snowfall for winter protection. With my thin soil, drainage is not a problem.
synergy--the rhizomes are supposed to be exposed, not the roots, but the bellies. Imagine chubby ladies sunbathing........
SDB Snickers.

This message was edited May 22, 2006 9:12 AM

This message was edited May 22, 2006 9:12 AM

SDB Car Hop

Bumble Bee Deelite

Grannymarsh,

Don't feel bad about your small rzs. Iris rzs will naturally shrink down in cold-winter climates. It's just their way of toughening up. It doesn't impact their bloom or growth potential at all.

At least some of the large commercial growers on the West Coast irrigate their iris fields. Those huge lunker rzs are pumped up with water, among other things. If I tried to do that here, I'd rot them for sure. The healthiest irises are the ones that are acclimated to your own growing conditions, regardless of rz size.

One summer I purchased MDBs and SDBs from two different sources - one on the West Coast and one in New England. The western rzs were comparatively HUGE and very healthy looking. The eastern rzs were about 1/4 the size (or less) and looked like little raisins. Almost none of the western rzs bloomed the first spring after planting. All of the eastern ones did! I believe it was just a matter of the small eastern rzs being acclimated to a cold-winter area before I purchased them. By the second year after planting, the western rzs had shrunk down and bloomed along with the eastern ones.

Size may matter in some earthly regards, but iris rhizomes ain't one of them. ;-)

Laurie

Too funny.
"It ain't whacha got, it's what ya do with it"

I prefer the smaller tubers. The bigger ones often rot here if they were "plumped up" before shipping. It just makes it longer before the darn things aclimatize to Iowa.

My 'Change of Pace' iris has a stem of dried-out buds. I had never noticed this before. Must be the crazy May weather!

Laurief, you made a good point. In fall of 2003 I ordered irises from Wayside and they are blooming this year for the first time! Fortunately, it was worth the wait!

Last fall my next door neighbor gave me some rzs, -- they are blooming this spring! I'm sure it has to do with their being used to the climate.

This message was edited May 24, 2006 11:30 AM

laurief
Thank you for your comments about rz size and adjusting to cold weather. I purchased irises for the first time this year and they are all from west coast sources. Now that I know that they'll probably take a year to adjust I'll not be too disappointed if I don't see much in the way of blooms next year.

That's all very interesting. The irises I ordered from Cooleys several years ago are mostly just blooming this year, except for a few...Solo Flight is an exception. It has huge flowers and bloomed right from the get go. I'll look for a nursery up north or northeast to order from next, I think.
Sharon

Thanks for the encouragment. I noticed that some of the rzs look dead in the middle but at the ends they look "plump" and are sending out new shoots. Is that a sign that I should dig them and separate the good from the bad? Don't get me wrong, it sounds like I'm in a hurry to dig but just the opposite is true. Thanks.