Was purple. Now yellow!

[bengal]

I know, I know....I have been told at least once before that irises do not and cannot change color. I'm no iris expert, so I know that expert is correct.

So, would someone please explain to me why a purple iris here is about to open yellow?

And not an attractive yellow either. How do I know it will not be attractive, even though the flower has not yet opened? Because it happened here once before, about 8 or 9 years ago, to a dark purple iris.

The one that is newly yellow is not a seedling.....It has three rhizomes at this point. It's in the exact same spot my purple one was in last year.

Color me puzzled.

[kHT]

bengal, I have plenty of the two tone purples if you want to replace this one?

[Garden_of_Mu]

It is extremely rare for an iris to sport, but by no means impossible. And some varieties are prone to it. Is a purple one going to bloom to compare it with? A true sport will be identical to the parent in every way except for color expression, so compare all the other characteristics and see if they match. Chemical damage can sometimes cause color shifting in irises too, but it usually deforms the flower as well.

[laurief]

As Mike said, sporting is extremely rare in bearded irises, so that would be my absolute LAST possible explanation for what you are seeing. Herbicide poisoning would be my first guess. It doesn't take much RoundUp drift to bleach a dark iris yellow or white for that bloom season.

There are other potential explanations, as well. I have written a FAQ that lists a number of other possibilities. You can find it here:

http://lfrazer.com/iris/faqcolorchange.html

Laurie

[John]

Wow, I had never heard of herbicide poisoning having this effect! Interesting. I did hear about it causing tetraploidy in diploid plants, if they were not actually killed...

Nice website, Laurie!

[bengal]

Mike and Laurie, that's fascinating, and I can't believe that that explanation didn't occur to me. I wish I'd taken photos of the iris last year, so that I could compare to this year's flower. As far as I can tell, the form is going to be the same; certainly the height looks about right.

Roundup -- that's interesting. I garden almost entirely organically. Although I've used Roundup only a very few times, for bindweed and poison ivy, I'd always apply it with a paint brush. But it occurs to me that stuff from the neighbors' yard may indeed have drifted over....

OTOH, I will say that the purple iris that became yellow many years ago has never gone back to purple. It's still the same unattractive yellow it's been for years.

[laurief]

It's much, MUCH more likely that a yellow iris rhizome somehow ended up in your garden than that your purple irises turned yellow. In fact, even if something as exceedingly rare as a sport did occur, it still wouldn't have changed the purple rhizomes to yellow. The original plant would still be purple.

One or more of the explanations in my website FAQ applies to your situation. You just have to try to figure out which one(s).

Laurie

[bengal]

Laurie, I just read your FAQs on iris color changes. None of the alternative explanations apply in my case. I have very few irises, and mosts were given to me by my neighbor; she grows only purple or purple/white irises. Does not care for yellow, and has no yellow flowers in her garden. (Both of us have very small, in-town, city-style gardens -- so we don't have iris gardens or iris patches containing hundreds of cultivars, as collectors or people with large gardens would.) Also, she's had those irises and only those irises for >10 years, and has not bought any new ones. Come to think of it, they were probably there when she bought the house ~15+ years ago. The other irises given to me were either purple or pure white. Also, the iris in question grows by itself in one of my daylily beds, and it's been by itself, untouched, unmoved, un-anything, for about 4 years. Also again, no kids, no dogs, a fenced-in yard. I'm pretty sure I'd know whether someone had planted an iris rhizome in it.

Since, in your and Mike's opinion, sporting is exceedlingly rare, I'm going with the herbicide drift explanation. My neighbor to one side employs a so-called landscaping company to do everything, and I don't believe there's an herbicide, fungicide, pesticide, or any other cide out there that they don't like.

BTW, you have a wonderful web site! I think I "need" to buy some irises from you!

[Garden_of_Mu]

I've been thinking about this and, though I am by no means an expert on color genetics, I don't think it is even possible for a yellow iris or a purple iris to sport to the other color. Sports are almost always because a gene has either switched on or switched off. To get yellow from purple it would have to switch off the yellow gene while switching on the purple and while not completely impossible I don't think it is very likely. The odds against it would be astronomical. I know of sports that are white from a yellow, purple plicata from purple broken color, and white from pink, but have never heard of purple to yellow (though the Honorabile family does mix it's purple and yellows they've never gone from solid purple to solid yellow).

[caliloo]

Hey Bengal!

COuld it be that one of the rhizomes came from me? I had gotten quite a few of NOIDS from the Boone Garden cleanup last year. We were splitting and relocating a lot of the irises and I ended up with a bag that had about 10 in it. Some of them are blooming YELLOW in my garden as we speak.

Just a thought since I KNOW I gave you some rhizomes, maybe it was from that batch!

Alexa

[John]

Mike, what if the purple gene just got turned off, could there be yellow (albeit an unattractive shade) already underneath? Take HONORABILE, for example, isn't there yellow under the purple/maroon?

[laurief]

I think you're right about the color associations with sporting, Mike. I've also been thinking about the experiences I've had with herbicide bleaching. Although I'm not absolutely certain about this, it seems to me that when a purple iris is bleached by herbicide, it turns white. Whereas when an orange, brown, or brownish red iris is bleached by herbicide, it turns yellow. Have you noticed the same in your experience?

Bengal, when considering possible causes of apparent iris color changes, you really have to consider all scenarios. I've had irises growing in my garden for 8 yrs without blooming. If I bought a new property that bloomed only purple irises for 8 yrs, I might be inclined to believe that only purple irises were growing there. Your friends may believe that they are growing and have shared with you only purple and white irises, but that doesn't necessarily make it so.

Laurie

[Garden_of_Mu]

John- If there was yellow under the purple it would be purple to begin with. When yellow and purple express together you get the red-brown like Honorabile's falls, if the purple turns off in H you get a yellow iris, ala Sherwin-Wright. if the yellow turns off in H you get a white over purple amoena.

Laurie - I've only seen herbicide damage in a purple iris and it did bleach it lighter purple to white and it was a gnarly flower as well - small and ugly. I've not seen one in a yellow iris.

I too have had irises not bloom for years on end and then suddenly they start and a surprise shows up. Last year my huge gorgeous clump of Goldfish bloomed for the first time since we moved in, and fully 2/3s of the clump was Tiffany. Given that Tiffany wasn't growing anywhere near my Goldfish in the previous garden I am at a loss to explain how it got there, but it did.

[laurief]

Mike, I have an interesting pic of a clump of Bit of Chocolate from years ago that caught some RoundUp while I was using a sponge brush to try to selectively kill weeds within clumps. I'll see if I can find it and attach it here. You can easily tell exactly which rhizomes in the clump got drips of RoundUp on them. The clump demonstrates everything from undamaged blooms to severely deformed and bleached blooms.

As far as "traveling rhizomes" are concerned, I've had that happen in my beds, too. Twice I've had cultivars show up in completely different parts of the beds than they were actually planted in. It took a couple of years of pondering before I finally realized that the deer were doing it. They'd pull up rzs, carry them off a way, then drop them. I'm still wondering where Beach Baby is going to show up. Some Bambi plucked up that rz years ago, and I keep expecting to find it blooming around here somewhere some spring.

Laurie

[bengal]

COuld it be that one of the rhizomes came from me? I had gotten quite a few of NOIDS from the Boone Garden cleanup last year.

Nope, Alexa, this one definitely came from my next-door neighbor, and I think maybe 4 years ago or so. Never been touched, never been moved.

Your stuff is planted near the little pond and in the little side garden.

Laurie, I do understand your frustration with my insistence that it could not have been an unbloomed yellow. (It's akin to someone stating that they'd bought a cobalt blue daylily, even after my telling them that such a thing's not possible. ) But I knew that garden for a couple of years before my neighbor moved in, and I know the very plant she gave me my original piece from. So we're now going back nearly 20 years. What are the odds that I received the only yellow iris in that garden that ever existed? Nah....I much prefer to contemplate an iris miracle.

BTW, the first flower opened fully today. It's far prettier than I thought it'd be - essentially a very pretty bright butter yellow. My camera died, else I'd have photographed it. BTW again, it's a different form and a different yellow than the other purple-turned-yellow I have. That one isn't near to opening yet.

Aren't I just driving you guys nuts?

[bengal]

if the yellow turns off in H you get a white over purple amoena.

Mike, do you mean you'd get something like this?

[Garden_of_Mu]

Exactly. if you turned on the yellow gene in both the standards and falls you'd have an iris like this:

(and Laurie - excellent photo! It perfectly illustrates what the damage looks like.)