Agro-K Science-Driven Nutrition™ from Tight Cluster to Pink Impacts Fruit Quality & Packout

Agro-K Science-Driven Nutrition™ from Tight Cluster to Pink Impacts Fruit Quality & Packout

Apple growers have limited windows of opportunity to positively impact their crop. One essential crop timing occurs from tight cluster to pink. During this period, Science-Driven Nutrition ™ is crucial for maximizing the yield of high quality fruit at harvest.

The ideal time to begin a foliar nutrition program is at tight cluster. Up until tight cluster spur leaf development has largely been driven by the plant’s nutritional reserves from the previous year. A proactive approach to nutrition will make all the difference to a grower’s packout.

During tight cluster, it’s important to support leaf development and function. This means having the right mix of magnesium, iron and zinc. Magnesium builds chlorophyll, the driving factor behind photosynthesis, while iron supports the chlorophyll development process. Zinc helps to develop the vascular tissue, leading to larger leaves. Bigger leaves mean increased sugar production and, ultimately, vibrant fruit color at harvest.  Agro-K’s Zinc +5 DL is designed specifically to support leaf and vascular development.

At pink, growers turn their attention toward optimizing the bloom window. There is a short period to get calcium into the apples in time for fruit cell division. It’s important to note that if calcium is not adequately applied from bloom until four-to-six week’s post-petal fall, the opportunity is lost and fruit quality can suffer. Any applications beyond this point act as nutrient maintenance and are essential to maintaining fruit calcium levels for fruit quality and shelf-life.  Sysstem®-Cal – a low pH phosphite formulation and Vigor-Cal™ (a sugar-based nutrient solution) are both formulated to penetrate tissue rapidly and completely at this key peak demand window.

Boron, which ensures pollen viability, pollen production, and flower health, s also is at peak demand at pink timing. When applied together, calcium and boron synergize to increase the uptake of both nutrients.  Agro-K’s Top Set D.L.® combines boron and molybdenum to support nitrogen metabolism and utilization, cell integrity, pollen viability and flower health.

Agro-K sets growers up for success throughout tight cluster to pink by arming growers with the knowledge programs and products they need to make smart decisions. This process begins with 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. Science -Driven Nutrition ™is implemented to determine crop nutrient levels and foliar product applications ensuring the apples get what they need to thrive.

For more information on using science-driven nutrition to help your crop flourish throughout the season, visit

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