Re: ROT -- more questions
- To: Multiple recipients of list <email@example.com>
- Subject: Re: ROT -- more questions
- From: VSpoon@aol.com
- Date: Sat, 15 Feb 1997 13:22:21 -0700 (MST)
Well, I wasn't going to respond to any more today but I couldn't resist.
Soft rot is caused by Erwinia carotovora which causes the rhizome to smell
very foul. By the time you spot it (leaves have turned yellow and fall over)
it may be too late to save the plant if it is a small one. The bacterium is
worse in hot, wet weather. The bacterium is also said to be in soils around
the world. See World of Iris page 336.
We use Agrimycin ( we put powder directly on the rhizome) and Benomil
(drench) if we see signs starting. As with any control you need to follow
directions and use safety precautions. Some people have a reaction to either
or both of these. Other controls are: garden in the desert ))), don't use
overhead watering, control insects (bites allow entry for the pathogen), be
careful when cultivating (garden tools can injure rhizomes), don't use a
fertilizer with a high nitrogen ratio, don't use manure as a top dressing
(okay if put under or into the beds), some people pour comet on the rhizomes,
keep mulches pulled away in the spring (we mulch with wood chips for winter
protection here in our zone 6), keep them healthy and divided. Hope this
zone 6 northern VA and this is the last one today I mean it.