Some of our earlier harvested varieties, like Blanc du Bois, in west GA have their harvest start scheduled very soon! While many of you still have several weeks before harvest begins, it is time to refresh on things to keep in mind when making harvest decisions.
Harvest Decision Considerations:
- upcoming weather (forecasted rain or storm coming?),
- the vine status thus far in the season (is your canopy happy and healthy or has the vine been suffering?),
- wine style goals (‘early’ harvests can produce lighter, more acid-forward wine)
- labor availability (can you get hands to help when you need it?),
- cultivar (are the clusters: thin skinned? tight clustered? rot prone?)
Repost from 2018 by Cain: https://site.extension.uga.edu/viticulture/2018/08/harvest-update-good-luck/
Deciding when to harvest: As I mentioned in the previous post – we may have to sacrifice some maturity for bringing rot-free fruit into the winery; this will be cultivar-dependent, and more attention will need to be given to thin-skinned, tight-clustered, rot-prone whites (Chardonnay, Pinot gris, Vidal blanc) and rot-prone reds (Merlot) relative to cultivars like Chambourcin, Cabernet Sauvignon, Cabernet franc, Norton, Petit Verdot, and Petit Manseng. Go out and scout for diseases. Taste the fruit. Observe the skin integrity and seed texture and color. Measure sugars, acids and pH. Use all tools (sensory, chemical, weather forecast) to make judicious harvest decisions.
Harvesting “early” can produce lighter, acid-forward wine styles (table/food wines, sparkling wines, rose wines, etc.). One may decide to take a conservative approach and pick some of the crop early to make lighter wine styles and hedge bets in hanging the rest of the crop in aim of making a full-bodied, round wine. Hanging fruit does not necessarily guarantee higher sugars, but does generally guarantee higher pH, lower acidity, and greater risk of fruit falling apart – keep this in mind when forecasting wine style goals and what will need to be done in the winery to amend unbalanced fruit chemistry. Yes – fruit with low Brix will need amended by chaptalization (sugar addition). But then again fruit with low acidity and high pH will also need amended with acids. Which is the right way, or the lesser of two evils? Not my place to say. But – please keep in mind that sugar is far from the only indicator of maturity; Brix should therefore not be the lone factor used to decide when to harvest. As you hopefully have over the past five months – pay close attention to the weather forecast. Please pick the fruit if it is creeping up in pH and falling apart and there is hurricane forecasted. However, your Cabernet franc and Petit Verdot might benefit from longer hang time if the fruit is rot-free and sunny weather is forecasted.
- See post about the wine grape acidity profile study at UGA that YOU can help – contact Abhinav Mishra – (706) 542-0994; email@example.com – https://site.extension.uga.edu/viticulture/2023/07/wine-grape-acid-profile-study-participation/
- August 16th – 11:30-12:30 ET – ASEV-ES Hang Time – Top most common mistakes when making wine. To hang, or not to hang? Are we really compromising phenols for just Brix?
- August 16th – Harvest Considerations and a discussion of ongoing seasonal issues – UGA Extension Event – In-Person Event at Limoges Cellars in Cleveland, GA, tentatively from 9:30 AM to 1:30 PM. We will tune-in to the ASEV-ES Hang Time session, dig deeper into those considerations for GA, discuss some other ongoing projects as well as check in with other growers about their own issues this season. Come join us for lunch.
- Harvest considerations – Another previous UGA Cain Hickey blog on 2017’s harvest https://site.extension.uga.edu/viticulture/2017/09/harvest-update-post-irma-harvest-considerations/
- Determining Harvest Priorities – Maryland Extension – https://extension.umd.edu/resource/determining-harvest-priorities
Let us know if you have additional questions!