Iris won't bloom

2 1/2 years ago, a friend divided her iris and gave me some. We have lots of healthy-looking foliage, but only 2-3 blooms. (Hers bloomed beautifully).

Is it possible I planted them too deep? I put some Bulb Tone on them last spring - do they need other fertilizer?

Thanks.

Irises may not bloom the first year. Possible deep planting--they are not buried like bulbs. Are the tops of the rhizomes showing.

Peckhaus, don't know if it would apply in your situation but....I also was given some irises by my parents 2 1/2 years ago, and they aren't blooming. Crowding can also cause lack of bloom. They have healthy looking foliage, but they are being crowded out by a nearby rose and some ornamental grass. I'm transplanting them tomorrow to my "good" flower bed. =)

You might look for a fertilizer with a higher middle number to force blooming. Bulb-Tone is only 3-5-3, and it is organic so it is very slow release, not like a chemical fertilizer. I use regular Espoma Plant-Tone when I plant, because it is organic it lasts a long time. But I also throw down some Green Charger Fertilizer 0-25-25 in early spring. I get it at the local farm and feed store very reasonable.

Thanks for the responses. Some of the rhizomes were showing, but not all. I lifted some and planted shallower.

The irises aren't being crowded out by anything else, but it is possible they are too close to eachother. Not sure...
Thanks for the fertilizer tip. I will apply in early spring.

Don't add the fertilizer in the spring until the spring crocus are blooming in your area. Then you can safely use it.

So what else do you look out for if you have no crocus.

They also need LOTS of sun....

If you are going to fertilize irises, feed them when they start into growth during spring. Then again after they have finished blooming. That is according to Schreiner nursery. Also, plants can't tell the difference between organic or chemical fertilizers. In either case you want the first number to be low since that is nitrogen. A 5-10-10 is good.

Edited to add that plant so that top of rhizome should be level with the ground. Irises can take 2 seasons before they bloom, depending on the maturity of the rhizome you were given.

By the way, I grew up in Douglaston, Long Island, NY

This message was edited Oct 27, 2010 12:07 AM

Dear Blomma,

Thanks for the helpful info. I couldn't see some of the rhizomes, so I raised them. It's also possible that some of them were babies. In any case, I hope for more blooms next spring, for they've been in the ground 2+ years now.