In episode 52 of the Vineyard Underground podcast, we had a Q&A to answer some questions from listeners about harvest time. Below are a few of the questions and their condensed answers. Listen to the episode for more detailed responses to all of your harvest time questions!
Question: When can I turn off the irrigation before harvest to concentrate the sugars?
Answer: Balance is key in irrigation. You want to provide enough water to support sugar transport to fruit without causing stress that stalls ripening or causes dehydration. To do this, you should limit irrigation post-veraison, monitor soil moisture, and adjust for heat. Avoid completely stopping water pre-harvest; instead, use water sparingly as needed to promote the healthy ripening of your grapes.
Question: How much do I need to irrigate post-harvest, before dormancy?
Answer: Post-harvest, you will need to tailor irrigation to help with the transition to dormancy. You may need to do deep water penetration to manage soil salts and toxins, especially in areas with water quality issues. Always make sure to avoid excessive nitrogen, monitor periderm hardening, and provide winter water if needed to avoid root desiccation and ensure uniform spring bud burst.
Question: What are some late-season strategies for heat stress protection?
Answer: To combat late-season heat stress, ensure regular irrigation for open stomates and cooling vine canopies to safeguard fruit cluster microclimates. Avoid abrupt canopy management post-veraison. For additional protection, consider shade cloth or kaolinite clay sprays to shield against sunburn.
Question: What should I do to extend hang time if my berries are splitting before they are ripe?
Answer: If you encounter berry splitting, you first need to assess the severity because this can be a serious issue. Extensive damage may require early harvest, possibly for sparkling wine or rosé. For minor cases, monitor for bacteria and wild yeast. You can also use biological controls or Oxidate 5.0 to manage microbes and control fruit flies with insecticides like Delegate WG to reduce the spread of microbes by fruit flies (always read the labels of all spray products and consult your crop advisor).If you want to learn more about harvest time, check out https://www.vineyardundergroundpodcast.com/vu052.
