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Vernal, Utah

A grower in my area has 3 plants with leaves that are yellowing. I will post a picture of them under my diary (Worker-Bee). He would really, really, appreciate knowing the cause and what to do about it. Thanks. WB

6/4/2011 6:59:21 PM

Buffalo, New York

maybe iron or n2.

I aint no pro though.

6/4/2011 10:03:07 PM

Vernal, Utah

Thanks Jeremy. I'll pass it on.

6/4/2011 11:07:42 PM

Midwest

I aint no pro but I have leaves lookin almost like that, yellow blotches all over and I think it Angular Leaf Spot (ALS). If those yellow areas turn brown, die and leave only the veins, then its ALS. OR, becuase I aint no agronomist, it may be lack of iron or nitrogen although the entire leaf would be light green and not show yellow blotches. You might have to search online for cucurbit leaf diseases. If its ALS, I don't know what the cure or if there is a cure. I use Daconil and Immunox together every 5 days to keep it under control. I think the best treatment is a systemic fungicide which I'm searching for. Best wishes

6/4/2011 11:50:38 PM

Muddy Waters

they say lack of magnesium can cause yellowing but this is extreme,I would like to know what you find out!was a soil test done? were amendments added??To much something or major lack of something?????.some leaves look normal but low on nitrogen???

6/5/2011 6:41:34 AM

cold soil

6/5/2011 8:36:46 AM

Www.extremepumpkinstore.com

I agree with Don, certain nutrients are unavailable when the soil is cold.
Magnesium deficiency isn’t as extreme as you would think; a Potassium deficiency can cause a Magnesium (and Nitrogen) deficiency by affecting the uptake of Magnesium.
Magnesium Deficiency is displayed as yellowing of the leaves between the veins with the veins remaining green...
A lot of growers are experiencing Yellow mottled areas; this can be a Manganese deficiency.

6/5/2011 11:13:49 AM

Www.extremepumpkinstore.com

A soil test is essential to balancing youyr soil, and get a fertilizer with micronutrients.

6/5/2011 11:17:22 AM

Germany

Cold soil, that´s what I would also think of first. Last year we´ve had a cool and misty spring, and my plants developed yellowish leaves within their first weeks in the patch. Later on, their leaves were beautiful, large and GREEN. Hence, it couldn´t have been lack of nutrients (in my case). Especially a few days or weeks after transplanting them into the patch, their should be some milligrams of each mineral available for a few green leaves, and I would expect lack of nutrients (Mg, Fe, Mn, K) at later stages. Cold soil, however, could slow down root growth, thus causing lack of minerals (by limited root capacity available for decent mineral uptake), although minerals should be available (according to lab tests).
This year I have treated my plant spots in a way which should help the soil warm up (see my diary), and I have covered them with some black stuff, just to get the sun warm up the pile even more (a few days before setting the plants there). No yellow leaves this year.

6/5/2011 2:37:02 PM

Www.extremepumpkinstore.com

*****Let me correct myself here- Too much Potassium (not a potassium defciency)can effect magnesium uptake (as well as Nitrogen and Calcium).
Next time I proof read before posting.

6/5/2011 6:46:29 PM

Vernal, Utah

Wow! You guys are great to respond. It has been cold and though Ralph (the grower) has the pumpkins protected, I would wonder about soil temp; it's been high 30's & low 40's all of April & May. He's working hard to do the right thing but needs more help. Ralph said he had a soil test done and it was fine(?). I have a feeling it was minimal (County Extension type). He and I have searched cucurbrit diseases and nothing quite looked like his leaves. I do appreciate all the suggestions and education for me as well. I've been pushing the Big Pumpkins website to him and singing your praises. Dori Perry

6/6/2011 10:07:13 PM

Owensboro, Ky.

WB & Ralph the grower!!! Hoping warmer temps, and hard work, will let you's guy's grow a BIG one!!! Peace, Wayne

6/7/2011 2:25:49 AM

Vernal, Utah

Wayne. Thx. We are still hoping for the warmer temps (it's getting colder and raining today)! The hard work never ends. The good news is that Ralph says his pumpkin is growing and the new leaves look ok. It's also had a female blossom--we only had 1 male blossom for him to use to pollinate.....

6/19/2011 7:55:18 PM

Owensboro, Ky.

WB, this early & prbly smallish plant...I wouldn't worry too much about only 1 male blossom!!! Prbly a couple more weeks of plant growth, will make for a better pollination!!! Both bigger plant to push pkn, and more males to help!!! Peace, Wayne

6/21/2011 1:57:41 AM