Expert: Long Island Gardener - 4/16/2008

Question
Can I dig up and replant Iris's right now. I live in Perris, California and my zip code is 92570.

Answer
I'm terribly backed up with questions, Kimberly, and I am trying very hard to catch up quickly.  Please accept my apology for taking so long to get back to you.  I hope you will still be able to use this information for your Iris plants.

Your Iris xiphium, 'Dutch Iris', prefer cooler temperatures and grow most vigorously in the Spring.  Peak metabolism is reached between 52 degrees and 62 degrees F -- way too cold for many plants, or even us for that matter.  But this also renders them more easily upset.

You can transplant if needed right now, so long as you are very careful about the kind of attention and treatment the roots are going to need.  Protect the lower portion of the plants from any mid-day heat, and try to keep them cool to the extent that is possible.

You should know that 3 weeks of temps in the mid- to upper-80s F will trigger dormancy in the Bulb.

Also, it is not unusual for these plants to be afflicted with blasted Buds when exposed to the wrong combination of heat, moisture and light.

The root-repairing plant hormone, marketed in garden centers as 'Messenger', may or may not work on Dutch Iris.  But if you can find it, it is certainly worth a try.  Cornell University holds the patent on this chemical, which triggers repair activity -- the kind you would find in roots of transplants.  It can be ordered on the internet.  Get the smallest amount you can find, as you don't need to use much to reap the best effects.

I hope this was helpful.  Thank you very much for your question.

L.I.G.