St. Vincent not ripening

[Ct Winemaker]

Hello Folks, we have St. Vincent grapes hanging (and wilting) on the vines (39 fully loaded vines). They just don't seem to be ripening, with Brix ranging about 12-14. They are however shriveling / wilting and have been in about this same range for weeks now. We're on the verge of frost here in north east Connecticut. Leaves are also dropping due to normal fall, so many grapes hanging with little to no leaves left on vines. FYI - this is our first year of harvest from our small vineyard. Chardonnel produced only about 1/3 of our expectation due to black rot (39 vines produced 12 gallons of wine), Marquette produce about 1/2 due to bee issues destroying the fruit (39 vines produced about 19 gallons of wine). Now St. Vincent not ripening, but heavily loaded with fruit.

Grapes seem way to sour to even consider wine making (even with significant chaptalization).

Anyone have any thoughts on this? What would you do? Anyone with St. Vincent, are they usually very late?

Thank you all very much for any thoughts or ideas you may offer.

 

[balatonwine]

It has been a weird year for most in the Northern Hemisphere. Some of my vines had significantly reduced harvests from prior years. What we did harvest, had numbers (pH, TA, Brix) very different from prior years.

Sadly, if this is your first year, you may need to call this a loss year. And hope things improve next year. If not, and if this is the new normal, then long term planning will be required.

If farming was easy, everyone would be doing it.

 

[Neb Farmer]

I do not grow St. Vincent grapes but from what I have read online, they ripen better when they are cluster-thinned ( green harvest ) . Basically the grapes may have a hard time ripening if ALL the clusters it produces are left on the vine. So, you thin them out, remove them, sometime around when veraison begins. Then the vine can concentrate on your remaining , hopefully best , clusters.
If you have a spectrometer, you could check the Brix level of the grapes and know for certain just where they are at , as far as sugar levels are concerned. It is nice to know! You may be surprised that they are riper than you think...or not. But if they are in the 17 Brix range , give or take a Brix level , you could probably make some decent wine from them, although you would have to add a little sugar to the must.
Also, if you are experiencing rot on your other grapes, you may need to consider spraying with sulphur or something else to minimize rot and mildew diseases. Some grapes are more susceptible than others, but check around your area to see what other vineyards are using.
Good luck with your vineyard and winemaking! ciao

 

[salcoco]

when I was growing St. Vincent I found it was necessary to do summer pruning to insure enough sunlight was reaching the grapes. also thinning clusters as suggested would also help.

 

[Ct Winemaker]

Thanks folks. Sounds like I should have thinned the clusters a bit. Neb Farmer, I do check with a spectrometer (only mentioned taste since I always taste will measuring in an attempt to roughly calibrate my taste buds). I also conduct a very complete spray schedule throughout the year (vines are extremely babied). If I could get 17 brix, I would be happy at this point! Terrible year here with the 2nd highest rainfall in history this summer alternating with extreme humidity and heat! Spraying and potential fungus was a constant and basically loosing battle this year. Bummer is, it was our first year to harvest.

Does anyone believe their is any sense in cluster thinning now? We probably have 2 -3 weeks before first frost.

 

[Ct Winemaker]

Confirmed by Double A, over Cropped! Lots to learn about growing grapes. Appearantly young St. Vincent vines are prone to that (3rd season in vineyard). Picked them today, 360 lbs from 39 vines, about 16 Brix. WiIl do our best with them- sweet low ABV wine.