Grapevine needs help to survive :(

[AJamin]

Hi friends and grape vine lovers.
I need advice from a professional in this forum on how to save my grapevines.
I planted 3 grapevines in my backyard 2 years ago mostly to provide shade. They grew healthy and strong the first 2 years but this year a disease is trying to kill them . The leaves are turning slowly yellow and dry after a while and the fruit didn’t grow much. I don’t care to much about the fruit itself but the leaves and the vine itself are more important to me because they provide shade to my back yard. I am not sure what it could be and how to control this. The verities are Flame Seedless Grape (Vitis and vinifera) and Thompson Seedless ( Vitis vinifera ).
This past winter was unusually colder, longer and more wet. We received lots of rain all the way to May which is very unusual for our area. I was told this unusual winter might have contributed to my vines problem.
Also I didn’t prune them to much since I planted them because I Wanted to keep the branches as long as possible for next season to provide shade. This didn’t cause any issue the first 2 years.
I live in California near San Francisco (Zone 9b). The original soil in my back yard was not good and I replaced all of it with a mix of 50/50 compost and garden soil 3 years ago.
I tried to avoid pesticides that are harmful to bees and sprayed the grape vine twice already with Organocide 3-in-1 (see picture below) but it didn’t do anything to save the vine. At this time, I would use anything to save my vines. Pesticides or mineral and or both or whatever it takes.
If you are a professional, I would appreciate it very much if you could offer advice on how to save my vines.
Pictures attached. I could only attach 10 pictures here but if you need more info please reply I and I will email you more.
Thank you all
AJ

 

[Rice_Guy]

* someone in California can tell you what exists in your area. The first place I look is my state extension agent, second is garden center owner, third is neighbors who have Vitis sp.
* your choices are fungal or virus. There aren’t lots of bacterial or nutrition plant diseases. Fungus, my savior is Mancozeb. Captan is easier to find but not as wide spectrum.
* Fungal, you shouldn’t lose the plant. Virus you should remove and burn. Moisture seasons are different so a dry year would look better,, also planting in gravel with good drainage would help.

Sorry I can’t be more specific. AND welcome to WMT

 

[SonomaPat]

I had a similar yellowing leaf problem that I posted a few weeks ago asking for advice. I also consulted the viticulturist where I purchased the vines who believed the condition was due to water stress.

Two things that have helped turn my vines around:

1. I increased water to 3-4 gallons per plant per week. I thought I could get away with less watering this year due to our rain.

2. I placed 1 Table Spoon of 10-10-10 fertilizer beneath each dripper to help feed the plant.

There is still a lot of growing season left for the leaves and they might be able to turn around.

Hope this helps.

 

[AJamin]

* someone in California can tell you what exists in your area. The first place I look is my state extension agent, second is garden center owner, third is neighbors who have Vitis sp.
* your choices are fungal or virus. There aren’t lots of bacterial or nutrition plant diseases. Fungus, my savior is Mancozeb. Captan is easier to find but not as wide spectrum.
* Fungal, you shouldn’t lose the plant. Virus you should remove and burn. Moisture seasons are different so a dry year would look better,, also planting in gravel with good drainage would help.

Sorry I can’t be more specific. AND welcome to WMT

Thank you for replying. I believe I should start with Mancozeb since Fungus is the only thing I would be able to control. And if that didn't help that I would assume it is virus? How many times/how long should I spray Mancozeb before I would re results.

 

[AJamin]

I had a similar yellowing leaf problem that I posted a few weeks ago asking for advice. I also consulted the viticulturist where I purchased the vines who believed the condition was due to water stress.

Two things that have helped turn my vines around:

1. I increased water to 3-4 gallons per plant per week. I thought I could get away with less watering this year due to our rain.

2. I placed 1 Table Spoon of 10-10-10 fertilizer beneath each dripper to help feed the plant.

There is still a lot of growing season left for the leaves and they might be able to turn around.

Hope this helps.

Thank you for replying. Are you located in California. Just want to know if 3-4 gallons / week would be sufficient in my area

 

[SonomaPat]

Thank you for replying. Are you located in California. Just want to know if 3-4 gallons / week would be sufficient in my area

Yes. In Sonoma, Ca.

 

[AJamin]

Yes. In Sonoma, Ca.

Can I ask you for the contact info viticulturist you consulted. The one where you purchased the vines. My area is residential and I don't think there are any viticulturists or vineyards where I live ( Fremont, CA )

 

[Want2bwinemaker]

Hi friends and grape vine lovers.
I need advice from a professional in this forum on how to save my grapevines.
I planted 3 grapevines in my backyard 2 years ago mostly to provide shade. They grew healthy and strong the first 2 years but this year a disease is trying to kill them . The leaves are turning slowly yellow and dry after a while and the fruit didn’t grow much. I don’t care to much about the fruit itself but the leaves and the vine itself are more important to me because they provide shade to my back yard. I am not sure what it could be and how to control this. The verities are Flame Seedless Grape (Vitis and vinifera) and Thompson Seedless ( Vitis vinifera ).
This past winter was unusually colder, longer and more wet. We received lots of rain all the way to May which is very unusual for our area. I was told this unusual winter might have contributed to my vines problem.
Also I didn’t prune them to much since I planted them because I Wanted to keep the branches as long as possible for next season to provide shade. This didn’t cause any issue the first 2 years.
I live in California near San Francisco (Zone 9b). The original soil in my back yard was not good and I replaced all of it with a mix of 50/50 compost and garden soil 3 years ago.
I tried to avoid pesticides that are harmful to bees and sprayed the grape vine twice already with Organocide 3-in-1 (see picture below) but it didn’t do anything to save the vine. At this time, I would use anything to save my vines. Pesticides or mineral and or both or whatever it takes.
If you are a professional, I would appreciate it very much if you could offer advice on how to save my vines.
Pictures attached. I could only attach 10 pictures here but if you need more info please reply I and I will email you more.
Thank you all
AJ

Looks similar to powdery mildew which is a fungus, and fungi thrive in wet conditions especially if air flow is poor which keeps moisture on the plants. If it is fungus, you can treat with neem oil. Just follow directions on container.

I had a bad case in my vegetable patch, and neem oil did the job.

Blake

 

[Cynewulf]

I would guess powdery mildew based on the photos and your location. Be aware that if it is, mancozeb is not effective against powdery mildew. You will need to spray with either sulfur or neem oil (not both).

 

[Snafflebit]

I think I see powdery mildew, which is quite common. Next year spray with micronized sulfur in water. There are also some cupped leaves and that may be herbicide damage