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)


Upcoming Events
Vegetable Field Meetings with Dr. Steve Reiners

July 14, 2025 : Herkimer County - Ivan Martin's Farm
Herkimer, NY
Topics: Tomato Fertility and Mitigating Physiological Disorders; Pest Scouting, ID, and IPM Field Walk.

July 15, 2025 : Washington County - Hand Melon Farm
Greenwich, NY
Topics: Tomato Fertility and Mitigating Physiological Disorders, Tomato and Sweet Corn IPM; FSMA Water Assessments and Postharvest Sanitation

July 16, 2025 : Ulster County - Wallkill View Farm
New Paultz, NY
Topics: Tomato Fertility and Mitigating Physiological Disorders; Veg Pest Update and Management; Cornell Tomato Breeding Program and Slicer Tomato Variety Trial Tour
2025 Berry Twilight Meetings

July 2, 2025 : Berry Twilight Meeting at Dressel Farms
New Paltz, NY
Join Heather Kase, CCE ENYCHP, and Anna Wallis, Cornell IPM, for seasonal updates on berry pest man-agement and IPM.

July 16, 2025 : Berry Twilight Meeting at Samascott Orchards
Kinderhook, NY
Join Heather Kase, CCE ENYCHP, and Anna Wallis, Cornell IPM, for seasonal updates on berry pest man-agement and IPM.

August 6, 2025 : Berry Twilight Meeting at Fishkill Farms
Hopewell Junction, NY
Join Heather Kase, CCE ENYCHP, and Anna Wallis, Cornell IPM, for seasonal updates on berry pest man-agement and IPM.
Champlain Valley Orchard Field Afternoon

July 17, 2025 : Champlain Valley Orchard Field Afternoon
Chazy, NY
This July ENYCHP will be hosting an orchard field afternoon highlighting Mike's research trials at Chazy Orchards.