Scouting Tips for Onion Thrips in Onions
Christy Hoepting, Extension Vegetable Specialist
Cornell Vegetable Program
To find the first thrips of the season, look deep into the leaf axils. Inspect 20 to 30 plants and count the total number of onion thrips (OT) per plant and divide by the average number of leaves per plant to get the number of OT per leaf. Thrips feeding causes silvery streaking along the leaves. If you can already see thrips feeding damage that is also a good indication that it is time to spray. If there is a lot of feeding damage, than you likely missed a timely first spray.



Scouting Tips for Onion Thrips in Onions (pdf; 239KB)


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Rochester Soil Health Field Day
September 16, 2025
Rochester, NY
Join us for a hands-on soil health field day! This event is for small-scale and urban growers, gardeners and farmers, with a focus on best practices for building soil health and cover cropping, and is a part of the 2025 Soil Health and Climate Resilience Field Days. It will offer valuable insights and hands-on demonstrations to enhance soil health.
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