The 2021 Honeycrisp Playbook: Early Foliar Calcium
Dan Donahue, Tree Fruit Specialist
Eastern New York Commercial Horticulture
Early is where it's at: Individual Honeycrisp fruits analyzed for mineral content around the end of the cell division period of fruit development (+40 mm) have been found to be highly variable in mineral content, particularly calcium. Four years of research results in the Hudson Valley show that early season fruit calcium content can vary as much as 4.2X from a low Ca fruit to a high Ca fruit (figure 1). These finding suggest that our calcium troubles start early in the growing season and therefore should be addressed early as well. The calcium cation is not very mobile with plant tissue and doesn't move from cells with a surplus to cells in deficit. Calcium cations need to be available for cell walls and membranes locally, and when needed. Too far away and/or too late is of little help. Since calcium plays a role within the plant in hormonal signaling, the cations cannot remain "free" within cell cytoplasm or within the spaces between cells and cell walls. Free calcium cations that are not incorporated promptly into cell membranes, cell walls, and endoplasmic reticulum are quickly deactivated and made unavailable through sequestration within cell vacuoles.
Early Foliar Calcium (pdf; 226KB)
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Upcoming Events
Rulfs Orchard Vegetable and Berry Field Meeting
August 4, 2026
Peru, NY
Join CCE vegetable specialists Elisabeth Hodgdon and Chuck Bornt for a vegetable and berry field meeting at Rulfs Orchard, in Peru, NY. We'll tour the farm's fields and talk about integrated pest management of sweet corn and cucurbit crops. Then, we'll view a drone demonstration and discuss new technologies for pesticide application and spotted wing drosophila management in berries. Light refreshments will be provided. A rain date will be announced if adverse weather is predicted.
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August 6, 2026
Johnstown, NY
Visit organic seed production trials and tour the farm to see small-scale production systems at work, including tarping, cover cropping, and the use of assorted mulches and covers to modify the growing environment.
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August 11, 2026
Rexford, NY
Join the ENYCHP and Cornell scientists on August 11 for the Capital Region Orchard Twilight meeting in Saratoga! We will be touring Bowman Orchards and reviewing seasonal recommendations for pests and diseases for apples, plums, and berries, as well discussing crop insurance.
NYSDEC Pesticide Applicator Recertification Credits: 1.25 in categories 22, 1A, & 10. Refreshments will be provided.
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