Agro-K’s Science Driven Nutrition™: Optimizing Apple Bulking with Foliar Nutrition

Agro-K’s Science Driven Nutrition™: Optimizing Apple Bulking with Foliar Nutrition

Growers have four main windows of opportunity to maximize their harvest as the apple crop’s nutritional needs change through the season. Apple bulking, when fruit cells expand and the apple increases in size and weight, is an important opportunity to impact fruit development. Growers who use Science-Driven Nutrition™ to better understand their apple crop can support optimal growth and an enhanced marketable yield.

A proper nutrition plan ensures cohesiveness throughout the growing season. Bulking is the period of time when growers must focus on facilitating the production and movement of sugars into the cell structures. During cell division, the crop timing prior to the fruit bulking window, growers increased calcium applications to support fruit cell development and fruit firmness. When this opportunity to introduce calcium into the fruit ends four-to-six weeks post petal fall, maintenance applications using products like Agro-K’s Vigor Cal™ or Clean Calcium, are required to support tree growth and fruit firmness.

In addition to supplemental calcium, the apple tree requires an increased amount of energy to support the rapid leaf expansion and shoot growth that occurs at this time.  Agro-K’s AgroBest 9-24-3 is an excellent source of phosphorous, which is a key nutrient behind the energy driving healthy cell development. Zinc assists with the leaf and vascular tissue development on the new growth, while magnesium, manganese, sulfur and iron synergize to maximize chlorophyll production and photosynthesis. Agro-K’s Zinc Plus +5 is a great example of a foliar product containing multiple micro nutrients designed to support leaf development and function during fruit bulking.

Potassium, which helps to move sugars throughout the plant and regulates plant moisture through the opening and closing of the stomata, is one of the most important nutrients during this time. The apple crop’s potassium needs increase exponentially during the summer months. Fruit color, weight and uniform maturity at harvest all hinge on maintaining proper potassium levels during cell bulking with products like Agro-K’s KDL and Clean Potassium.  Excessive nitrogen, an inhibitor to fruit color, must also be avoided during this crop window.

Science-Driven Nutrition™ was developed to help growers manage the apple’s diverse and complex nutritional needs by following the Five Rs: The Right nutrient applied at the Right time in the Right form in the Right mix targeting the Right location in the plant. This approach maximizes effectiveness and minimizes product waste.

During apple bulking, Agro-K’s soft foliar products ensure producers don’t inadvertently create fruit lenticel cell damage, a problem that inevitably worsens over time. Agro-K’s Vigor and Dextro-Lac product lines use a proprietary biological finishing technique that safely improves crop performance by enhancing nutrient uptake and utilization. Using soil testing, sap analysis, fruit sampling and other tools, growers determine which products will be most helpful for their unique orchard.

For more information on using Science-Driven Nutrition™ to help your crop flourish throughout the season, visit

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