Siberians do not look well

I have absolutely no experience with Siberian Iris but I have Caesar's Brother and Butter and Sugar. I was told to fertilize them in late Sept and early April with 10-10-10 which I did last year but have not fertilized them this year. They bloomed last year (but not much) which was the first summer after planting in Aug. '07. Right now the leaves are turning yellow but we have had very cool weather so far - 60's during the day and 40's at night. They get bright sun now but filtered later in the season. I am getting VERY discouraged with them. Any advice would be welcomed! I can post a picture later if that would help.

What is your soil pH? Sibs prefer an acidic soil. If yours is alkaline, that may be your problem. Sibs also like lots of water from spring through bloom season.

I, too, have Sibs that have been badly stressed by the late, cold spring. A few that had started to come up several weeks ago are now dying back - giving up, I suppose. Not much we can do about the weather, though.

There are certain soil nutrient deficiencies that can cause yellowing of the leaves. I'm trying to remember ... iron, maybe? I'm just not sure. You could check with your extension agent about that.

Good luck with those Sibs.

Laurie

It's not you. We are experiencing a late cold spring with stretches of warm almost hot days in late winter. I'm sure this stresses the plants. They don't know if they should grow or stay dormant. Even if they don't perform well this year they will usually come back next year and be fine.

In the spring of 2007 I visited my son in Ky they had no leaves on many of their trees. They had had a late killing frost and all the leaves curled up and turned brown. Some leaves came out as it warmed up but they were sparse and it didn't look good. He was devastated as he had just built his home in the woods choosing the location because of the beautiful older trees. Even though it was harder for the contractors to work he wouldn't let them cut down those trees.

When we visited this year the trees were just beautiful. Just be patient.

Thanks for the encouraging words! Yes, it's been mostly cold but then we did have a couple hot days thrown in too, I'm sure it does stress the plants. I'm just getting to pot up the annuals now because of the cold. They are stressed, the poor impatiens look pretty bad so they'll be better off planted I'm sure.

mittsy - Good for your son not allowing the trees to be cut down!!! That makes me crazy when they cut all the large mature trees down and then go and plant stubs for landscaping, what kind of sense does that make? I think the beauty of the property is in the mature trees. My husband's a carpenter contractor and we built our home 28 years ago now. Our lot was completely full of trees. We left all the large mature trees too and our lot next to us, we left pretty much everything, just cleared the little ones out. We are just outside of O'Hare Airport and anyone who comes over comments how pretty our area is - that they'd never guess this would be back here (we're near major expressways too) Our little bit of country until we can retire for the real thing.

We got that frost here too late last spring after have 70's and 80's weather. It was devastating. Now, that I remember, it was the first summer after planting the iris and they looked bad then too and then perked up and bloomed. I guess I'm fearing it was something I did but I guess not! Thanks again all!

Please do post a picture, but it just sounds like they are stressed from the cold weather. Maybe you had a slight frost after that warm weather?

This has been a couple of unusual springs.

I wouldn't worry about them. But do post a picture and let's take a look.

A shot of Miracid also might help. It won't hurt if you're soil is acid enough already, but will help if it's too alkaline. Put some on the leaves on a cool evening, when the next day is not going to be too hot and dry. It won't hurt them, no matter what, and might help.

If it was just the weather, you should be seeing some dark new growth at the sides of the plants soon.

If leaves are turning yellow, see if when you pull on them, they break off & come right out. That could mean iris borer which is more difficult to spot on the beardless plants. If they come off, dig a sample plant & check for borer grubs.

I doubt it's borers. Anything is possible, but siberians are least likely to get borers. If you see what looks like a pile of sawdust next to the plant, you might have borers, but the siberians fibrous roots are much less likely than bearded or even some other beardless to be affected by borers.

I have over 100 varieties of sibs, and have never had borers.

I think it's probably just the crazy weather this year. They could have gotten frost bit, they could have gotten too dry. I would still recommend a dose of Miracid. Keep them well watered.

Certainly Miracid is a good idea. Currier McEwen said he never had borer in siberians until he brought in roadside versicolor. Afterwards he had to battle them.

That's a shocker. I've had Siberian irises for so many years and have never had an iris borer problem with them and not with the JI's either.

So, leave versicolor alone. Dr. McEwen told that story on himself quite a few times. After all a borer should prefer the fat european rhizomes, chomp-chomp.

I think that the advice on soil is probably the correct bit. I just wanted to mention the other IF the leaves pull out easily as an alternate problem