The Texas Heat and Texas Grapes
For many Texans, it has been a scorcher! Grape vines like people thrive in certain climatic conditions. Grapes like cool nights with temperatures from 55 to 65 degrees. They like the day warm, but not scorching HOT! When the air temperatures go above 97 degrees, grape vines start to turn down their activity. When air temperatures reach 100 degrees or more, the grape vines will totally shut down as to photosynthesis. As the grapes vines shut down in HOT temperatures, the evolving grapes are impacted since the hot air cuts down on the sugar levels going to the maturing grapes. Texas winemakers and vineyard owners are carefully monitoring the daily weather to determine when their grapes are maturing and what the sugar levels are. Those sugar levels are important since alcohol levels are based on sugar levels. Too much sugar and the wine has high alcohol which produces an unsatisfactory burn in the back of your throat as you sip your glass of vino. Too little sugar and your wine might not have the aging prowess.

Here is what Texas winemakers and vineyards managers are saying about the current status of Texas grapes:
Ron Yates, Spicewood Vineyards
Before the summer heat set in, it looked like 2023 would be one of the better harvests we’ve ever had in terms of quality and yields. The extreme heat will move harvest up, possibly as early as July 15 for some whites. We will make sure to balance sugar levels with phenolic ripeness so that our reds, in particular, develop secondary and tertiary notes before we harvest them.
Dave Reilly, Duchman Family Winery
Given we never have a “normal” harvest, this year is turning out to be fairly normal. Spring was kind to the vineyards, giving us a great start for high quality and good yields of fruit. Our forecasted yields are coming in on target. We are excited to get our first harvest of Vermentino since 2016, which will help us get our popular white wine back into distribution. We are also excited about a bigger-than-normal crop of Sangiovese, which we didn’t get at all last year. Just like Ron and the others in Texas Fine Wine, we pick based on physiological ripeness to ensure we get the flavor compounds in our wines. If this heat settles, we will have a really good harvest, especially for reds.
Bob Young, Bending Branch Winery
Despite the summer heat, we are excited about this year’s grape crop from our estate vineyards and across the state. We expect a bumper crop from several of our vineyards and are excited to have our second harvest of Crimson Cabernet (genetic cross between Cabernet Sauvignon and Norton) from our estate vineyard. Last year’s Crimson Cabernet was harvested for a rosé that was just released to vine parents. After being on order for five years, we finally received and planted 800 vines of Camminare Noir, which is resistant to Pierce’s Disease and has characteristics of Cabernet Sauvignon and Petite Sirah.
With these high temperatures, the vines’ photosynthesis shuts down, which can throw sugar and phenolics out of balance. This is where our natural intervention tools like Cryo-Maceration (freezing) and flash détente (rapid heating and cooling), can help extract the phenolics from grapes during tough conditions like this summer. The grapes are going to appreciate getting to chill out after this summer of heat!
David Kuhlken, Pedernales Cellars
This year is looking to be one of our better harvests, with higher yields and really good quality fruit. A spring hail story in the Texas High Plains damaged one of the vineyards we work with, so we won’t be getting Graciano this year. However, we are excited to get Grenache, Mourvèdre, Syrah and Alicante Bouschet from the mostly organic Desert Willow Vineyards and our first fruit from our estate Kuhlken Vineyards since 2020. Everything leading up to this point has looked really good – our vineyards have enjoyed great vigor and canopy. While the heat is unfortunate, I am not overly worried about it compromising a good crop. It’s looking to be a good harvest for us.
The song (It’s a cruel, cruel summer) got it right this year with the sweltering summer heat doing a number on the vineyards. A cooler-than-normal, wet spring got things off to a wonderful start for Texas vineyards.
The consensus among Texas winemakers is this year’s harvest looks very good, with normal to better yields, and high quality, concentrated fruit. The challenge, if this heat continues, will be harvesting the grapes to balance both sugar ripeness with phenolic ripeness to ensure the grapes develop secondary and tertiary notes.