Missed our Thrips Identification Workshop? “How-to” Videos are Now Available Online!

*Characteristics needed to identify thrips to species.*

Although greenhouse growers’ thoughts in late summer tend to turn to pests of poinsettias, thrips are never fully forgotten (being the #1 pest and all).

Ever since a bunch of new thrips began invading North American greenhouses a few years ago, proper thrips identification has become a necessary evil. If you missed our Vineland/OMAFA Thrips Identification Workshops in 2024, have no fear. Ashley Summerfield from the Vineland Research and Innovation Centre has compiled much of the workshop content in a series of easy-to-follow videos. Keep reading for what you’ll need and links to the videos.

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GrowON Webinar, September 24th: Thrips parvispinus Control – Where We’re At and Where We’re Headed.

To make sure growers have the latest information on new thrips pests affecting greenhouse crops, GrowON is running a 3 part webinar series on thrips besides western flower thrips. The second installment will be on Thrips parvispinus (also known as pepper thrips) on Wednesday, September 24th with Sarah Jandricic (OMAFA).

To attend, please use the registration link in the post below.

Parvi poster Sept 2025_final Download

Description:

When it comes to Thrips parvispinus control, many growers are asking, are we there yet? Join us to learn where we are in terms of biocontrol and chemical control for this invasive pest. This presentation will summarize research being conducted in Ontario, Florida and Europe, and put it into context in terms of strategies growers can implement now. Future research directions will also be discussed.

Note, this presentation was given live at Greenhouse Canada’s Grower Day in June 2025. This webinar is hoping to reach those that weren’t able to attend in person!

Time: Wednesday, September 24th, 12-1pm

Registration:

Please register for Part 2 of this Webinar series by using this link: https://us06web.zoom.us/webinar/register/WN_30N3jt1KRbOyva0s7oh5Dg

NEW DATE: GrowON Webinar on Japanese Flower Thrips now Wednesday August 27th

To make sure growers have the latest information on new thrips pests affecting greenhouse crops, GrowON is running a 3 part webinar series on thrips besides western flower thrips. The first installment will be on Japanese flower thrips on August 27th, with Judy Colley (Plant Products) and Sarah Jandricic (OMAFA).

To attend, please use the registration link in the post below. If you’ve already registered, you’re still good for the new date of the 27th!

Setosus webinar poster July 2025 Download

Description:

Another new thrips on the block? Thrips setosus, also known as the Japanese flower thrips, affects hydrangeas, cyclamen, herbs and more. Judy Colley, technical lead for Plant Products, will share information on greenhouse trials for controlling this pest. She will be joined by Dr. Sarah Jandricic (OMAFA) who will cover biology, hosts plants, damage and current research. She will also go over pesticide options.

Time: Wednesday, August 27th, 12-1pm

Registration:

Please register for Part 1 of this Webinar series by using this link: https://us06web.zoom.us/webinar/register/WN_30N3jt1KRbOyva0s7oh5Dg

GrowON’s “More than Just Westerns” Thrips Webinar Series, Part 1: Japanese Flower Thrips

Over the past few years, we seem to be battling a whole new posse of thrips species. First it was onion thrips moseying on up into our chrysanthemums and gerbera. Then, it was Parvispinus, which was like a runaway train in our tropicals. Now, it’s Japanese flower thrips (Thrips setosus), riding into town on crops like hydrangea.

To make sure growers have the latest information on these pests, GrowON is running a 3 part webinar series on thrips besides western flower thrips. The first installment will be on Japanese flower thrips on August 20th. Read on for how to register for this free webinar.

*A lineup of thrips species that attack greenhouse ornamentals. Can you pick out the usual suspects from the new kids in town? Photo by A. Summerfield, Vineland.*

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In Case you Missed it: UofF Webinar on Latest Thrips parvispinus Research

On March 12th, 2025, Dr. Alexandra Revynthi’s lab (University of Florida) gave an amazing update on what they’ve been working on with regards to Thrips parvispinus. A lot of this was important basic knowledge about their biology, such as development time and survival at high temperatures. There were also quite a few lab and small greenhouse trials looking at potential biocontrol agents.

Some of this will be information we build on to create effective IPM programs for Parvi in the future. But some of these findings, you could put into use right now.

You can go watch the full webinar using the link in the full blog post, or read my summary notes and see what I thought were the important take-aways.

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High Quality Photos for Thrips Identification: Rating Phone Attachments.

This is a guest post by Avery Johnson (former OMAFA summer student and current M.Sc. student studying Thrips parvispinus) and S. Jandricic.

Having difficulty identifying thrips on sticky cards and need clear photos to send to your consultant or extension agent? Don’t want to invest in a microscope? Well, you’re in luck, because we’ve done the legwork to find some good alternatives to get high quality photos.

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Poinsettia Pests 2024: Whitefly, Mealybugs and Other Pests

Poinsettia are being potted up and pest issues are already popping up! Read on to see what pests growers in Ontario are seeing, and what to do about them.

Continue reading “Poinsettia Pests 2024: Whitefly, Mealybugs and Other Pests” →

Pesticide Rotation Guide for Thrips parvispinus in Canadian Greenhouses

By Sarah Jandricic (OMAFA) and Judy Colley (Plant Products)

*A female (left) and male (right) Thrips parvispinus on a mandevilla flower.*

With the arrival of mandevilla, dipladenia and hibiscus cuttings, now is the time to start planning your management program for Thrips parvispinus. Unfortunately, it looks like this pest is here to stay in North America, and in the tropical plant industry at large.

In this post, we’ll focus on pesticide rotations to manage pesticide resistance, as well as a few tips and tricks to make sure your pesticides stay working.

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“How-to” Video of the Week: Plant Washes and Other Tools to Make Detecting Parvispinus Easier

*OMAFA Summer Student Avery Johnson demonstrating plant washes on-farm.*

In this week’s “how-to” video, we’ll explore using plant washes on-farm.

Plant washes are a simple but effective method to detect low levels of critical pests, such as Thrips parvispinus.

Once you’ve washed out your pests, we’ve also developed a quick “decision tree” to help you easily determine if you’re dealing with Thrips parvispinus or another thrips pest.

Keep reading to find the link to the video and additional resources.

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Potted Chrysanthemums 2024: Dips, Thrips and Threats

Every year at this time, growers start to think about strategies to minimizing western flower thrips on their chrysanthemum crops. This year, Thrips parvispinus is causing extra concern, given that chrysanthemum is one of its reported hosts.

Although there have been no reports yet of Parvispinus damaging chrysanthemums in North America, it’s still good to exercise a bit of caution. However, jumping the gun and spraying chemicals will likely just disrupt your biocontrol program for western flower thrips, leaving you with a bigger mess on your hands.

This post contains information on things you can do to put your mind at ease about all sorts of thrips this chrysanthemum season.

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