The mild winter and warm temperatures in late February 2024 have pushed berry crop development along much further than in previous years, including last year. I visited a farm on February 28 that had accumulated 355 growing degree days (base 0˚C / 32˚F) from the time period of January 1 – February 27 2024.

I encourage everyone to check their berry crops and calculate the cumulative GDD (base 0˚C or base 32˚F) on the NEWA website for the weather station(s) closest to their fields.

On February 28, we pulled back 3 inches of straw mulch to see strawberry plants with young, bright green leaves. This is a sign that the strawberries are starting to grow for the season. If strawberries are kept under mulch long after they exit dormancy, there is an increased risk for foliar disease and crop loss. While we do use the mulch to protect plants from temperatures below freezing, starving the strawberries of sunlight is a greater risk to this season’s crop.

The ideal solution would be to remove the mulch, and re-apply it as temperatures dip into the range of 28 – 20˚F. The second-best option is to remove the mulch from dormant plants and let them photosynthesize through the cold.

Raspberry buds are still small and dry. Blueberry and blackberry buds are beginning to swell. Growers planning to apply delayed dormant sprays such as lime sulfur may need to do so earlier than in most years, perhaps as early as mid-March, depending on the status of their planting.

 

Anya Osatuke

aco56@cornell.edu

607 752 2793