Blossom Blast and Bumblebees
Amy Ivy, Vegetable Specialist
Eastern New York Commercial Horticulture
There are a variety of reasons why blossoms might blast on tomatoes. Blast is a dramatic term for when the blossoms die and fall off before fruit can set. Temperatures over 95, manganese and zinc deficiencies, and pepMV virus are all possible causes. Some plants even do some self-thinning and shed blossoms when their fruit load is too great. But this week was the first time I had heard of the concept of over-pollination, and it seems several growers are having trouble with this in their early, heated high tunnel tomatoes.
Bumblebees are ‘buzz pollinators,' meaning they shake the pollen out of the anthers by buzzing. They bite onto the anthers and then vibrate their bodies to shake loose the pollen. For an amazing video clip of how this works visit: https://www.youtube.com/watch?v=SZrTndD1H10 . Growers with heated tunnels can start their tomatoes extra early but they need to buy in bumble bees to pollinate since the native ones are not yet active.
Usually this process works fine but sometimes there are more bees than flowers and the hungry bees come back to the same flower multiple times, trying to shake more pollen loose. Too much of this aggressive feeding can kill the flowers (see photos).
One grower estimates he has lost half of all of his first flower clusters, a loss of about $2400, so this damage can be serious. The bee supplier has renamed its product line this year and most of our growers are ordering the ‘start-up' hive. But this hive was developed for high volume hydroponic producers in mind and has more bees than usual. I visited three growers with this problem this week and we would be very interested to know how many others are having this problem. Please call, text or email me (adi2@cornell.edu or 518-570-5991).
Photo: Notice the darkened anthers (blue arrows) and the dropped blossoms (red circles). A little bit of darkening is tolerable but the flowers will drop if this much damage occurs.
This article is from the April 26, 2018 edition of ENYCHP Vegetable News. To read the full newsletter, CLICK HERE.


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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.
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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.
2026 Winter Cut Flower Webinar Series
January 6, 2026
The fifth annual CCE Cut Flower Webinar Series begins on January 6, 2026 and continues over 5 weeks on Tuesdays. This is a very popular series of online events you won't want to miss, with topflight speakers, a wide variety of subjects concerning growing cut flowers and plenty of interaction between speakers and attendees.
Tuesdays 1pm-3pm January 6, 2026 - February 3, 2026 (The webinar held on February 3 will run 1pm-4pm)
Cost: $60.00 for all five sessions, $20 for single sessions
Webinars will be recorded, and all the recordings will be sent to registrants for future review.
Expanding Farm Sales: Markets, Profits, and Branding Series
January 10, 2026
Looking to diversify where you sell your farm products? This four-part workshop series helps farmers explore new opportunities in direct-to-consumer, wholesale, and institutional markets. Learn how to meet buyer expectations, price for profitability, and build lasting relationships that support your business goals. Participants will strengthen marketing and communication skills, evaluate which sales channels best fit their farm, and connect with buyers, distributors, and local partners who can help expand their reach. Whether you're just starting out or ready to grow your market presence, this program will help you chart the right path for your farm's future.
Four Session Series: Saturdays from 10AM to Noon, January 10-January 31, 2026
Attend at one of three locations: Schoharie Extension Center - Cobleskill, NY; Otsego Education Center - Cooperstown, NY; Via Zoom
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Any questions can be directed to Kelley Doolin at kmd322@cornell.edu
