Maximize Grape Quality with Targeted Applications of Potassium

Potassium (K) is one of the most essential nutrients in grape production. Although it is often mis-applied, there are effective ways to deliver K so that it can contribute to high-quality grape development.

Even though it is readily available in most soils, vines have difficulty taking up enough K to meet crop needs during peak demand starting at fruit set. Factors such as drought, deficit irrigation and high salinity can adversely affect the uptake of K. The lack of K in the early stages of grape cluster development can lead to smaller clusters, lower total soluble solids (°Brix), uneven ripening and poor color.

The key concept in K fertility is getting it into the vine early and often so the plant has time to metabolize it and translocate carbohydrates to berries. To achieve that, Helena Chemical Company has developed a two-pronged program using soil and foliar applications of K. The soil-applied portion of the program utilizes Nucleus® 0-0-21 or Nucleus 0-0-15. These products are designed to increase the solubility and mobility of K in the soil, a major challenge for conventional K fertilizers. The Nucleus technology package overcomes fertilizer inefficiencies and K fixation. Plus, its excellent compatibility with other liquid fertilizers makes it an ideal blending partner.

The cornerstone of the foliar program is a tank mix of ELE-MAX® K-Leaf® 0-0-30 and Utilize® PK. K-Leaf enters the plant quickly, and Utilize PK is designed to increase plant metabolism. As true liquids, they are much easier for vines to absorb than other foliar solutions that use flowable or micronized suspensions. K-Leaf is a clear, concentrated K solution that requires low application rates. It is compatible with most pesticides and other foliar nutritional products. Utilize PK contains a high concentration of GA-142, a known physiological activator that speeds up metabolic processes. This allows the vine to acquire and utilize higher levels of soil and foliar nutrients.

The combination of K-Leaf and Utilize PK drives K to the leaves where it can be metabolized and boost carbohydrate translocation to berries. This effectively delivers the required amount of K to vines during the most critical stage of berry development.

To find out more about this program, along with proper application rates and timings, contact a Helena representative.

- Paul W. Crout, CCA/PCA