Plant Disease & Diagnosis

  • close-up of plant leaf

Update: 05/12/22

The UNH Plant Diagnostic Lab is almost ready for you!

We are currently moving into our new space in Barton Hall on the UNH Campus.  We will begin to accept samples from the public in June.

Check back here for more updates, and to access our new and updated submission form as it gets closer to our opening date.

If you have any questions, feel free to reach out to the PDL’s new director, Dr. Emran Ali at or  the PDL’s diagnostician, Madeleine Hassett, at

In the meantime, growers may continue to send samples to the Maine Diagnostic Laboratory:

Please visit the University of Maine Cooperative Extension Plant Disease Diagnostic Lab website for submission forms and contact information.

UMaine Plant Disease Diagnostic Lab sample submission form

How to send a sample to the UMaine PDDL

You can also watch this video for tips on submitting samples to a diagnostic lab

Commercial clientele should contact the UMAINE lab directly.

Home gardeners should first contact the Extension Education Center

Phone: 1-877-EXT-GROW (398-4769)

We appreciate your patience and cooperation during this time of transition and appreciate your support for UNH Plant Diagnostic Lab and UNH Cooperative Extension!



Emran Ali, Extension Plant Pathologist, UNH
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