Rebloomers....secondary gain?

I planted reblooming iris for the first time this year, and I know I shouldn't expect them to rebloom. However, the foliage looks so much better than my other irises I don't think I'll mind if they don't. Is this usual with rebloomers? If so, I might restrict all my future iris acquisitions to the rebloomers. I haven't had to cut back any ugly leaves, they all look fresh and green.

I really don't notice any difference between the rebloomers and the others. You're just lucky, I guess! Or maybe the ones you planted got more fertilizer?

I have 15 "rebloomers", but the most I've even seen actually bloom in the fall is 6 one year. We had a cool wet August. Most years, I only see 2 or 3 rebloom. the foliage looks no different than my other iris.

Chances are the foliage looks so good on your newly planted irises because they haven't had time to become infected with your garden's pathogens. Wait until next year. They'll probably look similar to your other irises.

Laurie

Laurie, I thought my other irises were simply going dormant. Isn't that what they do in mid to late summer? I have back problems, so I'm not very conscientious about cutting them back. And so I thought the rebloomers simply weren't going dormant. I guess I have a lot to learn.

I'm not sure what irises do in NC, but here in northern MN they stay green all summer. The older, outer leaves of the fans may die, but new leaves continue to emerge from the centers. There are, of course, diseases that can cause leaves to get all spotty and/or to die, but healthy irises don't lose their fans during the summer (if that's what you mean by "going dormant").

Some iris cultivars are definitely more resistant to leaf diseases than others. I've never noticed a connection between rebloomers and disease resistance, but maybe there is a loose one.

Unless your iris leaves are unhealthy, you shouldn't be cutting them back. The plants need their healthy, green foliage to feed themselves for next year's bloom.

Laurie

Hmm...."all spotty"....do you mean like this:

Yes, that's not dormancy; that's fungal leaf spot. Some cultivars are more susceptible to it than others, but chances are that your new rebloomers will look very similar to your other irises next year. The fungal spores infect new plants when infected leaves are blown against uninfected ones or when rainfall or overhead watering splashes fungal spores around the iris beds or when infected garden tools or the gardener's clothing spread spores from plant to plant.

Fungal leaf spot doesn't typically kill irises, but it is unsightly, and severe infections can weaken the plants and cause a lack of vigor.

Laurie

Thanks Laurie. I suppose this fungus, like many fungi, does rather better when things are moist. For me, this is another piece of evidence that many of the plants the previous owners of this property chose are not particularly well-suited for our site. We are in the mountains of North Carolina and the weather is very wet. We are more like Seattle than Raleigh, which is over in the Piedmont area of NC. I have scads of E. purpurea and Rudbeckia devastated by what is probably aster yellow, a phytoplasm which is encouraged by moist conditions. And to get good tomatoes, local farmers have to build "tomato houses": three sided clear plastic shelters with covers that keep rain out and raise the temperature of the tomato plants' micro-environment.

I've been wondering if I wouldn't do better trying plants from the Pacific northwest or from wet places in the British Isles.

Actually, the PNW is part of the area that is generally referred to among irisarians as "Iris Heaven". Bearded irises do magnificently out there.

It is true that fungal leaf spot is more prevalent during hot, damp periods, but it is controllable with preventative fungal sprays, avoiding overcrowding of iris clumps, avoiding supplemental overhead watering, and keeping infected leaves or parts of leaves trimmed off of the plants. Or you can just do what I do and ignore it. As I said, it doesn't typically kill irises. It's just ugly.

Laurie

Thanks again Laurie. "Iris Heaven" sounds lovely!

I could definitely do better by my irises. They certainly need to be divided, and I should cut off affected leaves. Nature does the frequent overhead watering so unless I want to build "iris houses", I can't change that. I will not use fungicide because I and my little daughter walk and run through all our plantings, and I'd rather have spotty leaves than a toxic garden.

I agree with you, missgarney, about the toxic garden. I have numerous 4-legged family members who spend time with me in the iris beds, so I don't use chemicals except under extreme circumstances, and then I make sure everyone is tucked safely in the house until the label says it's safe to contact the plants again. I don't use fungicides because it's not necessary for the preservation of the plants. They can survive with leaf spot.

I'm a gardener who accepts the imperfect perfection of it all. Fungal leaf spot and bacterial soft rot are conditions to which irises will always be subjected, so I let those chips fall where they may and praise the survivors. If Ma Nature feels it's important to give us a sweltering summer with no rainfall, perhaps that's her way of knocking back the fungi and bacteria and shrinking down the rhizomes to toughen my irises overall. This is the most miserable summer weather I can ever remember experiencing here. It was also my most glorious and abundant iris bloom season ever. Ma knows what she's doing. Who am I to argue?

Laurie

Laurie, I agree with you. I keep my iris dry, give them lots of air and sun. We have sweltering heat and plenty of rain in my part of Iowa. Great for the weeds, huh?

Weeds??? Oh, are you referring to my beloved native companion plants? ;-)

LOL One gardeners "weeds" are another's "wildflowers".