Plant Disease & Diagnosis Services

diseased leaf

Update (8/11/20):

The UNH Plant Diagnostic Lab is still closed for physical samples.

We are working to reopen the UNH-PDL for mail-in samples only. Please check back on the UNH-PDL webpage for updates here (

During the transition, we will continue to process digital samples for plant problem diagnosis as we have since March:

Home Gardeners:

   Please contact us via or 1-877-EXT-GROW (398-4769), photos are encouraged and may help us identify weed, disease, or insect problems you encounter.

 For commercial producers/operations only:

   The Plant Diagnostic Lab is accepting digital samples sent by email to Submissions must include a completed sample submission form (fillable sample submission form) your name, phone number, email, and good, in-focus images.


The diagnostic services offered by the UNH Plant Diagnostic Lab include identification of plant pathogens, stress-related disorders and pests. The UNH-PDL is directed by the Cooperative Extension Plant Health Specialist and serves as a resource for information and examples for training and educational programs offered throughout New Hampshire and the New England region.

Detailed information about the available diagnostic services, prices, and instructions for collecting and submitting your plant sample can be found on the Submit a Plant Sample for Diagnosis page.


Download the submission form

Location, hours and contact information.