Non Flowering Irises

I have been given various irises (about 18 months ago) and while they look healthy and are multipying like crazy dont flower. Some have been planted in the ground but most into pots . I think there are 3 different types so cant work out why none flowered last spring ?
Thanks in advance ,
Holty....

What kinds were you given? What are your winter temps?
Inanda

The information at this link may provide some possible answers for you:

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

Winter temps overnight 4 to 8 degrees C . I dont know the types but saw them in flower when I was given them from a similar area.

And again . This type has multiplied 8 to 10 fold from one 12 inch pot !! but not flowered . I say this in flower when I was given it .

It looks like (to me anyway) that those iris need to be divided. Sometimes if they are overcrowded, they won't bloom.

Are they in enough sun? It looks as if they might be in shade.

Your nights are getting almost to freezing. Unless the days are very warm, they won't be blooming. Also, since they are in pots they almost surely will need to be fed. Have you done that? Pot grown plants get depleted easily. Then, when were they in bloom when you bought them? What time of year. Were they in the ground and in a similar situation? Your plants look big and healthy but you're on the other side of the world so it's a little hard. Could you tell us a little about your climate?

Some are singles in pots and others are multiple planted up to 4 . They get sun all day until very late. Winter daytime temps 15/20 C , summer daytime can get up to high 30s C .Because I have so many and most are in pots it would be very easy to do controlled tests and compare the results . I like to fertilizer thoughts , I used a premium potting mix but it may need help , Again thanks for your help , Open to all suggestions .
John....
From memory I think the 1st photo are white double ruffles that only get 10 12 inches high if this helps anyone.

Now here's a question. Those leaves are so lush and green, I'm wondering if you might be feeding a fertilizer that is too high in Nitrogen. Nitrogen will feed the green parts of the plants at the expense of flowering if it is too high.

N is the first number in fertilizer formulas and your formula should be no higher than 6-10-10 if you are using a commercial product.

Hello! I was surfing the forums and found this one, and thought I'd chime in....

They look to me like they might be planted too deep. You know the rhizome part likes to sit on top, and only the ROOTS should be underground. If they are planted too deep, the rhizomes don't get "cold" enough to set blooms... at least that's my experience, and I'm in z7 in NE Arkansas. As a matter of fact, around here you could just about throw them out on TOP of the ground and they'd do fine. The roots will grow down into the dirt and as long as the rhizome is on top of the ground, they bloom just fine.

This may have been mentioned on the thread linked above, but I must admit that I'm lazy and didn't go look. Hope you have better luck with them next year. They appear to be perfectly healthy and that's the only reason I could see, since they get plenty of sun, that they wouldn't bloom for you. Keep us posted!
Gail
(Edit..... well I went to the link and voila! There was the note about them possibly being too deep!) lol

This message was edited Dec 25, 2005 5:58 PM