Hi

Would help to know what kind of Iris ?? The usualy problem with a plant growing but not flowering is not enough sun, Or if planted a long time maybe need thining?? gary

Ditto to what gary said. All of my water irises grow incredibly fast. They need to be thinned often and fertilized.

I think you may want to get your irises out of the pots. They are fast growers and will rapidly need to be divided in the pots - and anytime you divide them they take time to get re-established and start producing blooms again. Can you plant them somewhere in your pond where they can naturalize? I think you'll find they will grow much faster and bloom better out of the pot, and they will be more beneficial to your pond at the same time.

They also don't need to be put into the bottom of the pond over winter - as long as the roots are under water they are hardy and will be fine.

I believe that these are standard Siberian irises. They never bloomed here, where I live, until I put them in my pond. Last year I'd divided the clumps into 3 pots and had lots of beautiful flowers. I am afraid to fertilize because I have someone gotten filamentous algae in the pond which I am currently trying to 'fix' with AlgaeFix, hornwort, anacharis and some water hyacinth.

I have no fish so there isn't a huge nitrogen load. They seller sent me a great big bunch of hornwort and I have high hopes for that. I have used one dose of Algae Fix and I think I'll dose it again today as it has now been 3 1/2 days since the last dosing.

I also just put in a small plant of copper iris but it is the first year for it and I don't think I'll get flowers until next spring or maybe even the spring after that.

I don't think I can put them in the bottom of my pond since it is a liner pond with no gravel or planting medium. Right now they are in 10-inch pots and setting on plastic milk crates so that the tops are out of the water but the bottom of the pots are in the water to a depth of 2 or 3 inches.

How many 'stalks' should be in one pot? And is there any way of fertilizing that would not promote algae growth?

I have never fertilized before, but then my pond will be just 3 years old in August so I am still learning as I gol

I think you are right; I just compared photos of 2014's spring with those taken this year. The plants are MUCH larger. Here they are for you to look at. 2014 is first; then 2015.

Trying to figure out how to load a photo.

Okay, those are both the same photo with irises visible in central part of the right hand portion of the frame. I will try to load the other photo showing them this spring which, for some reason, did not upload previously.

Even I can see that the irises are HUGE in comparison with last year's version, which bloomed mightily.

Should I re-pot now? Or wait until fall?

THANK YOU!

Your pond is so pretty! It looks very natural in that setting.

You can divide them now. They're past the point where they would bloom if they were going to anyway. And I agree - you can't put them in the bottom of your pond, as it would be too deep for them anyway. But if there's a way you can plant them out of the pots (like between the rocks, on the pond side) it would be better for both the irises, as they would be able to spread more naturally, and better for your pond, as plants IN the water are better able to take up nutrients from the water which would help with your algae issue.

I am not a fan of chemical algae fixes. To use it effectively you should be removing as much of the string algae as possible by hand before you treat. If you don't, all the dead algae in your pond will simply perpetuate the problem of feeding more algae. So if you have to remove it manually anyway, then what's the point of using the chemical? Number two - chemicals don't just kill the algae. They kill lots of the little microscopic critters that live in, and help balance, your pond ecosystem. Even without fish you have a lot of life in your pond. Chemicals, in my opinion, only keep the bad cycle going.

Work to balance your pond and you will find your water clears up. You said you have no fish, however look at all the trees and organic material that surrounds your pond. Any of that that ends up in the pond contributes to the conditions that algae loves. Consider the algae just a symptom - it's not really a problem in and of itself. Other than being unsightly that is. But it's telling you something about your pond and is in fact working to help clean it up.