Hi I'm new to the forum. A bit of background then come the questions.
I have had iris for years, only a few old varieties that I've paid little attention to and have thrived. So, I decide since they're such no brainers I'd put in a new bed just for some of the wonderful and varied hybrids you can buy on line. Last fall I planted about 20 and most of them bloomed this spring non lost to pests or disease. I'm encouraged so I order A LOT more. The first batch I planted in early July right before the monsoons started, I live in W. Pa. I ordered form 4 different nationally recognized growers, all planted within 2 weeks of each other. So far I've lost 20 new iris to bacterial rot all from one grower! My first question is, are some iris more susceptible to rot because of, region they came from, fertilizer used, etc. or is this just a coincidence? Second question, can I treat the soil with sulfur or copper or anything else to make sure there's no bacteria left in it?
Ps, I've never been on a forum before so let me know the correct etiquette. Thanks

Butterandjam, Sorry to hear you lost so many. Most reputable dealers will replace them for you. It could be a coincidence that most of the ones that rotted were from the same provider. Were they all planted in the same area? If your soil is too acid, you can have more rot then normal. I haven't experienced too much rot in newly planted irises in the fall year of their planting, seems I get more of that in the spring if we have a lot of freeze and thaw weather. If they were all mixed up with other vendor's plants, and the others were OK, that would be a different story. I do think that some irises are more susceptible to rot then others.

Yes, they are mixed among last years iris and the iris from other growers and in 4 separate beds yet I only lost iris from the one vendor.....?.?

I have big gaps where the diseased iris were taken out anyone know if I need to treat the soil in those spots?

The high heat and large amounts of rain you just got probably helped cause the rot. Spray all your remaining iris with fungicide as a precaution. If it was bacterial soft rot, but you caught and removed the rotted iris quickly, then you shouldn't have to do any heavy treatment of the soil. Add new soil in places you add replacement iris. If you are concerned you can spray the area the iris were located with a bleach solution, enough to saturate the soil, to kill the bacteria. 10 to 20% bleach to water ratio will not harm the iris still in the garden.

There is some argument about how long soft rot bacteria will stay in the soil. The older belief is that it sticks around, the newer thought is that the bacteria dies out after it's food source (the rotting rhizomes) is removed. Still a trial and error situation in my book.

Thanks for your help

Carol!

carol!

to the Iris Forum Carol!

Carol ~ to the Iris Forum!

I hope that you will get some compensation from the iris vendor regarding your lost irises.

I've found that some irises acclimate better to a new climate than others. If and when they do adjust usually it's smooth sailing going forward. This year I decided to put up all my new acquisitions so that they develop root systems before planting, just to give a little more strength starting out. The dwarf irises I just put right in the ground since overall they tend to be more hardy.

Good luck and welcome!

to the forum Carol

Carol! Are the Irises that rotted all right next to each other? The reason I am asking is if it's possible one had a disease and it spread to the neighbors?

Also your etiquette is just fine. These are good people out here and they put up with my iPhone hunt and pecks

There are plenty of opportunity for pathogens to spread when you divide and process irises for shipping.
Failure to sanitize tools between cuts, could spread pathogens easily.
Washing or soaking rhizomes together in a tank of some sort seems potentially dangerous too.

If pathogens are present they would probably develop much more easily if planted during a wet and rainy period. A vendor growing in an arid area might never have problems themselves and may not even be aware that there is a problem, but in a different climate it could be a different story.

Iris4U's greenhouse branch in Europe started putting their irises in a greenhouse because they had problems acclimatizing their Colorado grown irises into the excessively moist German climate. Read what they say themselves here:
https://www.iris4u.de/en/about...

They still import the rhizomes they sell by mail order from Colorado and personally I have had much more success with their irises once I realized I needed to keep their irises fairly dry the first year.