Re: Rotten Experiences-- Lengthy
> I am convinced that wet is more important than temperature as a catalyst to
> rot. Raised beds are vital.
Your above message is so true. As some of you are aware and to those of
you who are not, California does not get any rain from April thru
September. Not any! Well in the six years I have been here we did get a
half inch from a freak storm that came up from Baja. Anyway, we get two
types of rot here in California (yes there are different rots from
different agents). Soft rot caused by the bacteria Erwina carotovora
and crown rot caused by a fungus Sclerotium Rolfsii. You all in colder
climes probably do not experience Sclerotium Rolfsii as it is usually
restricted to warmer climates. To make my point when I see rot in my
field (either Soft or Crown) all I have to do to stop it is turn off the
spigot. Treatment is another story. There is no foolproof way of
curing Soft Rot. I dig the affected clump, cut and destroy all bad
tissue, let dry a few days, dip in a 5 to 1 clorex solution and plant
back in the fall. This usually works for me. Before I used the clorex
solution the same variety would get soft rot the following year.
I suspect the bacteria was established in what I thought was cured
rhizomes. Crown rot is easier to treat. Clorex solution "will" kill
the fungus on the plants. However the fungus may still be in the soil,
so solarizing/fumigating must be done if you plan on planting in the
I realize that those of you in other parts of the country where it rains
in summer don't have control over moisture. If I were you, I would
still dig affected plants and let them dry in a cellar, barn or
somewhere out of the rain and treat as above.
I can't expound enough on good farming practices when growing iris.
Planting iris in the same location each year will produce a buildup of
bacteria, fungus, insects which all love iris. Plus the added
depletment of the soil will make them even more suceptible to these
agents. Rotate your iris at least every three years. If not possible,
solarize your existing beds. If you can't do either of these then you
should not be complaining about rot.
Rick Tasco, Farming iris in California
12+ inches of rain in the past 24 days and still raining.