Ever wonder if removing leaves from young vines speeds up their growth? Spoiler alert: it doesn’t. In this blog post, we put five grape growing myths to bed and give you the clarity you need to nurture a thriving vineyard. Learn what the top five misheard grape growing concepts are – and find out if you are guilty of practicing any of them.
5. Removing Leaves on Young Shoots Will Enable the Shoot To Grow Faster
Many new grape growers mistakenly remove mature leaves from young shoots, believing it helps the vine’s growth. However, mature leaves act as ‘solar panels’, create carbohydrates, and support nutrient movement, which is essential for young leaf and shoot development higher up on the shoot. Additionally, removing damaged leaves can be counterproductive as even these can contribute nutrients and carbohydrates to the vine. It’s best to let them ride out the remainder of the season until natural leaf drop occurs. That way, you can fully utilize all of those nutrients and carbohydrates they still have to contribute to the vine as a whole.
4. Severe Shoot Hedging Just Before Harvest Makes Harvest Faster & Easier
While light hedging before harvest can definitely speed up the process by removing excessive growth, you don’t want to overdo it. Removing more than 25% of a vine’s active mature leaf area as it prepares for winter dormancy risks depleting essential resources and carbohydrates needed for root and trunk development. Ideally, only the top 10 to 15% of shoot tips, consisting of immature leaves or non-contributing laterals, should be trimmed. This may also remove the most susceptible young tissues from diseases like powdery and downy mildew without significantly impacting the vine’s health. For a balanced approach, ensure the canopy remains extensive enough to support vine development, particularly in high wire or vertical shoot position systems.
3. Competition From Undervine Cover Crops Is Good for Vines
Undervine cover crops can be beneficial or detrimental to a vineyard, depending on various factors such as vine age, vigor, soil type, and rainfall. For young vineyards (1-3 years old) lacking a full canopy or stationary growth structure, cover crops could compete with the vines for nutrients, inhibiting development. Conversely, in mature vineyards (four years or older) with ample water, soil nutrients, and a history of vigorous, uniform growth, undervine cover crops can moderate excessive growth. They are not recommended for vineyards struggling to achieve full canopy or in high-vigor situations unless used primarily to control soil erosion or improve organic matter accumulation during dormancy, particularly on steep slopes.
2. Apply Complete Fertilizers When Your Vineyard Is Low in Only One or Two Nutrients
Complete fertilizers supply balanced nitrogen (N), phosphorus (P), and potassium (K), which is important for young vines with limited root systems. Excess fertilizer, particularly N or K, can lead to unwarranted vine vigor, impacting fruit development and causing dense canopies prone to disease. It’s best to apply them only when plant tissue tests indicate a deficiency of all three NPK nutrients. Applying too much can also obstruct the uptake of other nutrients, such as magnesium or zinc, due to competitive absorption. As vines mature, precise nutrient management based on soil and tissue analysis is vital, potentially only requiring specific nutrients rather than complete fertilizers. Adapting fertilization practices to the vines’ developmental stage and nutritional requirements ensures better vineyard health and minimizes the ecological impact.
1. Waiting As Long as Possible To Prune Is Best
Delaying vine pruning can mitigate frost damage but may lead to a rushed final pruning job at bud burst, especially in large vineyards or with limited labor. Waiting too long may also reduce fruitfulness, particularly if delaying pruning until after shoots are over two inches long. Instead of postponing entirely, consider pre-pruning to remove excess canes early. For spur-pruned vines, leave longer spurs during early cuts, then quickly trim to one or two buds closer to bud swell. This approach allows for some delay while avoiding the pitfalls of last-minute pruning and potential crop loss.
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