Ah, but whatever it is that struck WAS fatal to the plants. Swift and deadly. Very disappointed in the charantais -- all those plump melons ripening in the sun and them BAM! foliage was decimated. I managed to get one melon, but it was relatively tasteless -- not terrible, but on par with what you get at the grocery. IDK if that's due to the cooler than normal night temps we've had pretty much all summer and the deluge of rain, or the disease. I got more than enough cukes before it hit, so no big loss there. But I want to avoid getting it again next year, whatever it was. My clips and pruners are soaking in a bucket of bleach solution as I type. Sounds like I can just leave the fences be. I do rotate their location every year (they're easy for DH to move, they're just cattle panel attached to T-stakes).

What to do depends on your winter temperatures and the type of disease. Some diseases need living tissue to survive, some can produce spores that will live on plant debris. Some survive freezing, some die off in winter and are restablished the next year by airborne spores or insects (such as the case with bacterial wilt). If you can pinpoint which specific disease you had then you can more accurately predict its survivability in your area. If you want to play it completely safe then you could spray with bleach, or if you have a flame weeder you can go over your cattle panels with that (carefully, obviously).

All that said, I've never done anything with my fences and trellises.

Rodney

Yep, with Rodney here...it can be really tricky, finding out exactly what pathogen is the cause but I have never done anything with trellis/fences/obelisks and so on either. I reckon and boots and braces approach is prolly worth doing - have never used either bleach or peroxide - I have, however, used a horribly noxious disinfectant called Jeyes Fluid which always seemed to do the job,

I don't think fences have a lot to do with it. Whatever infection you're up against is bacteria or fungi in the soil. Long ago, there used to be handy and easily obtainable compounds that could be sprayed on soil to kill EVERYTHING in it. Most of those are banned these days to everyone except certified applicators. Remember vapam? Be careful, because some of those soil sterilants last a long time. You might get in touch with your local extension and see if they know of any mitigation strategy for those diseases. Best bet might be just rotation, where you plant your cucurbits somewhere else for a while. To the extent they need cucurbits to survive, the diseases will die out naturally.

By the way, be sure to destroy those infected plants completely. DO NOT compost them!

"By the way, be sure to destroy those infected plants completely. DO NOT compost them! "

I threw everything in the trash. I really have no idea what it was, so IDK how to avoid it next year other than rotation, which I do anyway. Interestingly, it did not affect any of my squash or watermelon plants. Just the cukes and the melons. The cukes and melons were planted in in the same north-south row, with the charentais about 10-15' to the south of the cukes; the squash and watermelons were in rows to the west of this row, I'd say maybe 30' to the west. Is that some sort of clue?

It's just so odd that it hit all of a sudden and that was that. Usually there's some sort of indications of the beginnings of something, but not with this. At first I thought the neighbor sprayed Roundup or something and I got hit by drift, but then I realized he doesn't spray and I'm too far away to do that much damage simply from drift (on acreage so we're not on top of one another). Plus nothing else was affected.

ETA: I should've snapped pics to show you guys what it looked like, but I didn't...aaargh!

If you had cucumber beetles this season then they could have infected your plants with a rapidly spreading wilt disease that you describe above. If no cuke beetles were present then.......never mind ;-)

Well, the clue there is that the infected area is limited. That's good to know if it is soil-borne.

But bacterial wilt sounds right. "Cucumber bacterial wilt is caused by the bacterium, Erwinia tracheiphila, and is characterized initially by wilting and drying of individual leaves, especially those exhibiting cucumber beetle injury. Cucumbers and muskmelons are more susceptible than pumpkins or squash; the disease is rarely a problem on watermelons."

https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/pests-and-problems/diseases/bacterial-spots/bacterial-wilt-of-cucumber

There is also a page from University of Minnesota extension that says basically the same thing. It is carried by cucumber beetles, and does not survive in soil, except for a short time in plant debris. It will not overwinter in a cold climate like yours EXCEPT in the gut of cucumber beetles. Management of cucumber beetles is the mitigation strategy.

"Shriveled, brown, and dying" doesn't sound like bacterial wilt. Bacterial wilt makes a plant look severely dehydrated. As in droopy and wilted (hence the name). The leaves may brown and dry out eventually but the plant would be a goner well before that happened.

Rodney

No, it didn't look anything like wilt. From what I've read, if it indeed was downy mildew then the spores can't over-winter in the frosty north. So that's good. I grew Marketmore cukes, which are not resistant to DM. So I may have to try a different variety next year -- but dang both DH and I really liked this variety, and it was a prolific fruiter until they got suddenly wiped out.

Cattle panels in Michigan? You can skip sanitizing. Make sure any debris is brushed off well. If you got any rust, hit that with rust treatment. Cattle panels can stand up to a lot, but you never know. You could have some chasmothecia stuck on them. If you can move them off the spot they are on, do so and leave them out overwinter. Clean the plot extra well once the area is clear.

It's no gaurentee, but sometimes a deep cleaning helps.

That is good to hear a couple of you say to skip spraying down the fences -- one less thing to do.

Very simply, any diseases (bacteria, fungi and carrier insects) that can live on a fence can live just about anywhere in the bed. In a cold winter, it's a whole lot warmer in soil than it is on a fence. As noted below, it's a whole lot harder to sterilize soil than it is to sterilize a fence.

I agree with Daninthedirt, the fences are not going to matter much.