Plant Disease & Diagnosis

  • close-up of plant leaf

Update: 06/25/21

The UNH Plant Diagnostic Lab will not be accepting samples as of June 1, 2021

As of June 1, 2021, all NH plant diagnostic samples should be sent directly to the University of Maine Plant Disease Diagnostics Lab, and not to the UNH Plant Diagnostic Lab.

Samples submitted to the UNH-PDL after June 1 cannot be processed (and cannot be forwarded to UMaine due to decomposition and loss of quality of the sample in transit).  Submitters will be requested to send new samples to the UMaine Lab.


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)


This temporary change is necessary due to the retirement of the UNH Plant Health Specialist/Director of the UNH Plant Diagnostic Lab (Cheryl Smith). We are in the process of filling this vacancy.  

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



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