zuchini leaves

I am in zone 6 and am having problems with a couple of my zuchini plants. The leaves are curling up and turning brown. It's only been hot here a couple weeks now and we've been getting a lot of rain. It's raining every week so I haven't had to water very often. It looks like they are burning up but could they be getting too much water? The rest of my plants look fine - tomatoes, eggplant, cucumbers, beans, and peas. Thanks

That is a tall order without a close-up photo. You could have a pest or disease. Otherwise, only if you have no drainage could rain affect the plant directly. You might have something more exotic, but here are some common culprits and links to pictures and descriptions:

Scab - a fungus - can be caused by moist conditions and low temps.
http://vegetablemdonline.ppath.cornell.edu/factsheets/Cucurbit_Scab.htm

Picture of scab:
http://vegetablemdonline.ppath.cornell.edu/PhotoPages/Cucurbit/Scab/Scabfs3.htm

Mosaic virus - are the fruits misshapen? This can be spread by aphids.
http://images.google.com/imgres?imgurl=http://veg-fruit.cropsci.uiuc.edu/Events/IPD/Handouts/Virus%2520Diseases%2520of%2520Cucurbits_files/image002.gif&imgrefurl=http://veg-fruit.cropsci.uiuc.edu/Events/IPD/Handouts/Virus%2520Diseases%2520of%2520Cucurbits.htm&h=264&w=348&sz=50&hl=en&start=5&tbnid=SHEW_0eEwVHZWM:&tbnh=91&tbnw=120&prev=/images%3Fq%3Dmosaic%2Bvirus%2Bzucchini%26gbv%3D2%26hl%3Den%26safe%3Dstrict%26client%3Ddell-usuk%26channel%3Dus%26sa%3DG%26ad%3Dw5

Powdery mildew - Light powdery look; use a fungacide to control.
http://images.google.com/imgres?imgurl=http://www.nysaes.cornell.edu/pp/resourceguide/images/2_13_400.jpg&imgrefurl=http://www.nysaes.cornell.edu/pp/resourceguide/cmp/cucurbit.php&h=354&w=400&sz=81&hl=en&start=14&tbnid=oFvqUedbC1WnBM:&tbnh=110&tbnw=124&prev=/images%3Fq%3Dpowdery%2Bmildew%2Bzucchini%26gbv%3D2%26hl%3Den%26safe%3Dactive%26sa%3DG

Downy mildew - Yellow blotches; use a fungacide.
http://images.google.com/imgres?imgurl=http://vegetablemdonline.ppath.cornell.edu/Images/Cucurbits/Downy_News/DMZucchini.jpg&imgrefurl=http://vegetablemdonline.ppath.cornell.edu/PhotoPages/Cucurbit/Downy_News/DownyFS7.htm&h=392&w=400&sz=20&hl=en&start=3&tbnid=iR1ThVD5ITOqUM:&tbnh=122&tbnw=124&prev=/images%3Fq%3Ddowney%2Bmildew%2Bzucchini%26gbv%3D2%26hl%3Den%26safe%3Dstrict%26client%3Ddell-usuk%26channel%3Dus%26sa%3DG%26ad%3Dw5

Squash bugs - Hand pick, they will be visible; they can wreck your plant in a hurry.
http://images.google.com/imgres?imgurl=http://ipm.ncsu.edu/ag295/pics/squash_bug.gif&imgrefurl=http://ipm.ncsu.edu/ag295/html/squash_bug.htm&h=330&w=263&sz=18&hl=en&start=9&tbnid=yE5ZGDL-6JRKPM:&tbnh=119&tbnw=95&prev=/images%3Fq%3Dsquash%2Bbug%26gbv%3D2%26hl%3Den%26safe%3Dstrict%26client%3Ddell-usuk%26channel%3Dus%26sa%3DG%26ad%3Dw5

Squash vine borer- are there holes and frass ("sawdust") near the hole? They are hard to control.
http://images.google.com/imgres?imgurl=http://ohioline.osu.edu/hyg-fact/2000/images/2153_1.jpg&imgrefurl=http://ohioline.osu.edu/hyg-fact/2000/2153.html&h=270&w=521&sz=65&hl=en&start=14&tbnid=LgGDrvyg33mPdM:&tbnh=68&tbnw=131&prev=/images%3Fq%3Dsquash%2Bvine%2Bborer%26gbv%3D2%26hl%3Den%26safe%3Dactive%26sa%3DG

Striped cucumber beetle? They can cause bacterial wilt.
http://images.google.com/imgres?imgurl=http://www.hort.uconn.edu/Ipm/veg/pics/Strcucbtlelg.jpg&imgrefurl=http://www.hort.uconn.edu/Ipm/veg/htms/cukbtltcrop.htm&h=509&w=720&sz=54&hl=en&start=2&tbnid=Mz4cTqls5FdjSM:&tbnh=99&tbnw=140&prev=/images%3Fq%3Dstriped%2Bcucumber%2Bbeetle%2B%26gbv%3D2%26hl%3Den%26safe%3Dactive%26sa%3DG

Bacterial wilt - destroy infected plants.
http://images.google.com/imgres?imgurl=http://www.ca.uky.edu/entomology/entfacts/images/bacwilt.jpg&imgrefurl=http://www.ca.uky.edu/entomology/entfacts/ef311.asp&h=191&w=350&sz=44&hl=en&start=2&tbnid=Udb2ymnmECTf3M:&tbnh=65&tbnw=120&prev=/images%3Fq%3Dstriped%2Bcucumber%2Bbeetle%2Bbacterial%2Bwilt%2B%26gbv%3D2%26hl%3Den%26safe%3Dactive%26sa%3DG

We have had most of these things and it's no picnic to deal with.

(Please, if these long links are a no no here, somebody tell me).





This message was edited Jun 6, 2008 5:21 PM

Wow. Thanks for all the links! Here are a couple pictures. Sorry - it was raining before so i couldn't get to them. I get good drainage, and I was trying something new this year - growing up a trellis. Anyway, I didn't see anything that looked like my problem from the links you sent. I'll post a couple more after this

and one more to come

here is the last one.

Well, I'm still thinking - out loud - from the photos it looks more like a bacterial wilt than anything else. Have you seen any striped cucumber beetles on the plants? The beetles are about 1/4 inch long and transmit the disease. The bacteria clog up the stems so the leaves can't get moisture. Sometimes the stem sap will be yucky and slimy.

Also, try looking at the leaves with a magnifying glass, especially the undersides. Do you notice any fuzzy fungal growths?

These leaves drying out - like they're scorched - can be from heat stress, but it doesn't sound like you're having that.

I wonder if it could be a nutritional deficiency - sometimes, for example a nitrogen deficiency, can cause similar-looking symptoms. Do you think the pH of your soil is OK? But, if your other plants are OK, this might not be it either.

Another possibility - There should be an extention office somewhere near you - why not call them and find out if and when you could take a sample to them for their expert opinion. Another thing I've often done is consult the giant "Ortho" book available at many garden centers - it has good photos.

It's baffling because, otherwise, your zucchini looks so healthy! Glad your other plants are doing well. I enjoy a good mystery, but I'm stumped, max!