Crown Rot Help!

14 years ago

So I've been having trouble this summer with what I assume is crown rot. After we had all that rain this summer, I started noticing all sorts of water/humidity related problems, including plenty of powdery mildew and rot! I have heavy clay soil in a raised bed which I have amended with peat moss and top dressed with compost. Anyway.

I had some Arizona Sun blanket flower that ended up being planted a little too close together...each plant got larger then the seed packet said. So I'm sure that didn't help. Then all the rain. Then the last week of heat seems to have really done them in, because one by one, they are going all floppy (usually just one side first) and then I can easily pull the plant up...the stems just pop off at ground level. I've been cleaning up the debris as best as I can.

I went out and looked at one of my liatris spicata today; I had noticed that some of it's spikes had flopped over, and when I tugged on them, they popped right out!! Argh!! The leaves on those stems also look very floppy, like they haven't been watered in days.

So I have 2 questions. For one thing, if this is crown rot, it doesn't really look like the pics of crown rot that I've seen. There is maybe a VERY slight pale brown color down at the bottom of the stem (inside) but the rest of it looks perfectly healthy. The leaves and everything look healthy..very little yellowing. The crown does not seem to smell like anything but dirt. There isn't really mushy anything. Is this crown rot?

Secondly, if this IS crown rot, am I going to have a major problem next year? As in, will this over winter and I'll have the same plants-dying issues, except that it might spread more?

I'm getting pretty paranoid - tug-testing pretty much everything that looks remotely floppy...it just seems to keep popping up!

Sort by:Oldest

Comments (3)

oilpainter
14 years ago
Here is the blurb on crown rot from my saved collection of plant diseases. I hope it helps

Â Water-mold root, stem, and crown rot (fungus)
Symptoms: Roots or lower stems and crown decay.
Tops wilt, yellow, or die back. May occur on seedlings or
in the bed.
Control: Improve planting site drainage. Remove and
destroy infected plants. Begin seedlings using sterilized soil
and clean equipment. Soil drenches containing ethazole,
fosetyl-Al, metalaxyl, propamocarb, or ethazole + thiophanatemethyl
will prevent infections. Read the label for lists of
specific plants allowed for each fungicide.
Â White mold (fungus)
Symptoms: Plants collapse following a soft, mushy
decay at the base of the stem. Dark, irregular sclerotia resembling
small raisins may be found inside the rotted stem.
Control: Remove and destroy infected plants and sclerotia
weeper_11
Original Author
14 years ago
Hmm..I have to say I definitely haven't seen any of these "raisins." I just don't know what else this would be, other than crown rot. What else causes plants to break off at their base within a day or two?
valleyrimgirl
14 years ago
I don't think you have crown rot, or the whole plant would be going yellow and then falling over.

You should check the soil around the plant in the area that the limp stalk was. I had a few of the June Bug larvae chew off the plant stalk of an obedient plant and some thistle. I couldn't figure out why they were limp with the same symptoms you mentioned, and when I pulled them out of the ground, the larvae were right there at the top layer of soil. As I had gloves on, I squished them right away.

Google 'June Bug larvae' and see if you have any of these guys in your yard.

BTW, June Bug larvae also eat other bulbs, like lilies, and roots of perennials. Not such a good bug to have in your yard.

Brenda