Grape ripening time running out?

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That’s rough it’s warm today 85 finally it’s been 60’s or 70’s and hasn’t gotten warmer all year so finally seeing some warmth is going to be good for our grapes we have a lot of fruit under contract so I am anxious to get it into the winery because if it takes too much longer we might not get good grapes.
We went from 80's (when I tested) to low 50's at night to mid 60's day and rainy now for a few days. I'm hoping we get back to warm!
 
Fingers crossed for you! I’m hoping to pick Syrah today. Brix was 26 on Thursday morning but ph was only 3.22. I’ll test first thing this morning but also can’t wait much longer as birds and bees are just hammering the grapes.

We have low pH across the board on the grapes so will need to deal with that this winter.
 
Fingers crossed for you! I’m hoping to pick Syrah today. Brix was 26 on Thursday morning but ph was only 3.22. I’ll test first thing this morning but also can’t wait much longer as birds and bees are just hammering the grapes.

We have low pH across the board on the grapes so will need to deal with that this winter.
malolactic fermentation will take care of it. Be careful at 26 brix that you don't choke ML bacteria with high sulphite at high alcohol due to high brix.
 
Here in Murrieta, CA I cut my losses a few weeks ago after the 3rd consecutive week it dumped rain on my vines since the day tropical storm hillary dropped 2.5 inches in 24 hours. My Merlot came in at 24 brix and Cab at 22, but my Zinfandel was covered in scattered green berries. Rather than wasting hours trying to make a tiny batch of just the ripest berries, I crushed it all. The must was a measly 14 brix, so I ended up adding many lbs of sugar to take it up to 1.090. After primary, I pressed the skins of my merlot and Cab first, then dumped the skins in the press basket with the zin must to throw in some of that extra color and tannin that it was missing. I don't have high hopes for the zin at all, but worst case scenario if it tastes terrible in a year then I may pitch it.

Aside from the weather, I'm pretty sure there's another factor affecting my zin ripening. Year after year I've watched the leaves on my mature zin vines go from a nice healthy green to dark red by the end of the season. This doesn't happen to any of my other varietals. Additionally, I have a new row of zin vines which I sourced from a different nursery and I noticed this year that although I dropped almost all clusters since they are young, they didn't turn red at all. So long story short, I'm fairly confident all my other zin vines are infected with red blotch. Interestingly, I'm seeing almost the same pattern on that last picture from Dave, so im wondering if that could be a contributing factor as to why ripening isn't completing. From what I've red, that is one of the big problems with red blotch, it minimizes sugar production and delays ripening, but never actually kills the vine.

Here's a few pictures of my zinfandel vines this week. You can see the distinction between their color and that of the other healthy vines.

Personally, I'm planning to rip this row out and start over this winter, which sucks because these are 10 years old, but they've always had problems ever since the first year they carried a crop.
 

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I am not sure it is red blotch but it looks like a virus of some kind. Grapevines can live a long time with virus but they always seem to linger and produce poorly. In a marginal growing condition the vines die and the problem takes years to develop. Sorry to see it. I do not trust vines to be virus free unless they are from certified growers. Even then, infected vines have been know to slip through, but growers have a protocol to check for that happening.
 
I am not sure it is red blotch but it looks like a virus of some kind. Grapevines can live a long time with virus but they always seem to linger and produce poorly. In a marginal growing condition the vines die and the problem takes years to develop. Sorry to see it. I do not trust vines to be virus free unless they are from certified growers. Even then, infected vines have been know to slip through, but growers have a protocol to check for that happening.
Yup, I'm not totally sure if its red blotch either but it's pretty clear these particular vines will never get better and are just taking up space / time / nutrients at this point so they gotta go. I bought all 6 from Armstrong nursery in Temecula the same season, so its likely that they are all cuttings from the same infected vine. At the time I certainly didn't realize the consequence of buying vines that may not be from certified growers, but I sure know that now. The good news is that over all these years the disease / virus hasn't likely spread to my other vines, which I also planted the same year and show no signs of this issue. Live and learn...
 
Don’t want to hijack my own thread, could this to be a mineral/chemical deficiency, not a virus? Every year, I have big beautiful green leaves and the edges start going red just about veraison time. Very few get to the stage yours are at being totally red. Yours are also concentrated is one area? Mine do the red around the edges from verasion to the leaf fall off at the start of winter.
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Don’t want to hijack my own thread, could this to be a mineral/chemical deficiency, not a virus? Every year, I have big beautiful green leaves and the edges start going red just about veraison time. Very few get to the stage yours are at being totally red. Yours are also concentrated is one area? Mine do the red around the edges from verasion to the leaf fall off at the start of winter.
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Potassium or Phosphorous deficiency, try a soil test it will identify the deficiency
 
@David Engel Here is a picture of a Cab Sauv vine that has similar red coloration. I have flagged this arm for removal because I found Eutypa on a pruning cut. So you could have something wrong with that spur or cane. I think you said this is Merlot, which is not very subseptable to Eutypa but it is worth thinking about.

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Don’t want to hijack my own thread, could this to be a mineral/chemical deficiency, not a virus? Every year, I have big beautiful green leaves and the edges start going red just about veraison time. Very few get to the stage yours are at being totally red. Yours are also concentrated is one area? Mine do the red around the edges from verasion to the leaf fall off at the start of winter.
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Ha! Yeah sorry, it wasn't my intention to hijack your thread, I was trying to point out that your leaves look similar to mine so I was suggesting that "if" this is red blotch in both cases it may explain why my zin didn't ripen and neither are your grapes. It's possible in your case it's a deficiency, but in mine it's unlikely given that all my other vines are fed and watered the same way but don't have the problem.

One other side note on your situation, another contributing factor along with the lack of heat and sunshine may be overcropping. Depending on how old and vigorous your vines are it may be a good idea to drop clusters early in the season before berry set. The general rule I've gathered is thin to one cluster per cane if the plant is 3 years old, 2 per cane if it's 4 years old and then you can increase the clusters per cane from there if the plant is very vigorous.

I admittedly overcropped my zin vines this year, not based on their age but based on their vigor, I really should have dropped all but one cluster per vine given how taxed they look at the end of each season.

At this point I'm not sure if cluster thinning would do much for you, but early in the season it can help keep the vine balanced so it doesn't struggle to ripen a lot of fruit.
 
@David Engel Here is a picture of a Cab Sauv vine that has similar red coloration. I have flagged this arm for removal because I found Eutypa on a pruning cut. So you could have something wrong with that spur or cane. I think you said this is Merlot, which is not very subseptable to Eutypa but it is worth thinking about.

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Yeah that's looking pretty close in appearance. The varietal I'm having issues with is zinfandel, my merlot is totally fine. Thanks for the tip, I'll look into Eutypa.
 

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