Watch Those Temperatures
Chuck Bornt, Team Leader, Extension Vegetable Specialist
Eastern New York Commercial Horticulture
Just another reminder that even though we haven't reached really concerning temperatures yet, temperatures in high tunnels, crops under rowcovers or especially those under clear plastic hoops (such as sweet corn) can get very hot on these gorgeous bright sunny days! For sweet corn, the larger the plant under that plastic the greater the risk of injury is. If it gets too hot under that plastic, consider piercing the plastic with a pitchfork or setting up and running the irrigation to cool the soil and plastic. If it looks like we are in for a long warm stretch, you might consider slitting the plastic and removing it altogether. The one benefit of using floating rowcovers on sweet corn compared to plastic is you don't have to worry about it getting too hot as the rowcovers naturally breathe and are cooler. The following information is from Dr. Steve Reiners of Cornell University Department of Horticultural Sciences and can be used as a guide to know when to remove covers before it's too late!
"Most of the published temperature guidelines list maximum temperatures at which either vegetative growth becomes limited or reproductive capabilities are threatened, i.e. flowers or fruit fall off. Temperatures at which vegetable plants may die varies and depends not only on the vegetable type but also on other factors such as whether irrigation is being provided or for how long the high temperature occurs. Also, a transplant will be under much greater stress than a plant that is direct seeded.
The following table lists temperatures at which severe stress will occur, possibly death, especially if soil moisture is low. These temperatures refer only to potential crop death. Temperatures 15 to 20F lower than those listed in the table will result in the loss of flowers and fruit and will negate the positive effects of early warming under row covers."
Chart with various vegetables
Row cover
Apples
Apricots
Asparagus
Beets
Blueberries
Broccoli
Brussels Sprouts
Cabbage
Carrots
Cauliflower
Cherries
Cucumbers
Dry Beans
Eggplant
Ethnic Vegetables
Garlic
Grapes
Horseradish
Kohlrabi
Leeks
Lettuce / Leafy Greens
Melons
Nectarines
Onions
Parsnips
Peaches
Pears
Peas
Peppers
Plums
Potatoes
Pumpkins / Gourds
Radishes
Raspberries / Blackberries
Rhubarb
Rutabaga
Snap Beans
Squash - Summer
Squash- Winter
Strawberries
Sweet Corn
Sweet Potatoes
Tomatoes
Turnips
Upcoming Events
Ag Labor Road Show IX
December 1, 2025 : Save the Date! - Ag Labor Roadshow Webinar 1
In addition to the in-person Ag Labor Roadshow program in our region on December 9, two webinars are scheduled for December 1 and December 22. Each webinar will focus on different program content that is different from the in-person sessions. These webinars are an added benefit to program registration.
December 9, 2025 : Save the Date - Ag Labor Road Show In-Person Event (Greenwich, NY)
Greenwich, NY
The Roadshow delivers essential updates on labor law, regulations, and workforce best practices—tailored for farm owners, managers, and ag service providers. Sessions also focus on practical strategies to boost communication, strengthen retention, and build a positive workplace culture.
The in-person session for Eastern NY is December 9 - Elks Lodge, Greenwich, NY - full day in person session
Additional in-person sessions are:
December 10 - Hilton Garden Inn, Watertown, NY, December 17 - Cornell AgriTech, Geneva, NY, December 18 - Genesee Community College, Batavia, NY
December 22, 2025 : Save the Date! - Ag Labor Roadshow Webinar 2
In addition to the in-person Ag Labor Roadshow program in our region on December 9, two webinars are scheduled for December 1 and December 22. Each webinar will focus on different program content that is different from the in-person sessions. These webinars are an added benefit to program registration.
How to Obtain a Pesticide Applicator License
December 17, 2025
Thinking about becoming a certified pesticide applicator in New York, but aren't sure where to start? Join DEC representative Kenneth Klubek for a discussion on who needs to become a certified pesticide applicator, certification types, examination procedures, and recertification. Participants will have ample opportunity to ask questions during the program.
Pesticide Applicator Certification Exam Prep Course
January 13 - January 14, 2026
Join ENYCHP specialists for an in-depth review of topics covered on the NYS DEC pesticide applicator certification exam. This two-day virtual course includes explanation of key concepts on the core exam, test-taking tips for the core and category exam, practice questions, and Q&A with instructors. Course materials, including program recordings, practice exams, and DEC materials will be available to registrants after the program. This training is geared toward certification categories 1A (agricultural plant), 21 (field and forage), 22 (fruit), and 23 (vegetable).