Plant Diagnostic Lab

  • close-up of plant leaf


We are open! Please read below for more information.
 

The UNH Extension Plant Diagnostic Lab will open on Monday, June 8, 2026. At this time we will only accept samples from commercial growers, businesses, municipalities, state and federal agencies, and agricultural and natural resources service providers.
 
To submit a sample, please contact your local Extension field specialist or state specialist for a referral to the lab. Please note that at this time we cannot accept mailed samples, and all samples must be accompanied by a referral. 
 

For in-person assistance, Plant Diagnostic Lab staff are available on Mondays, Tuesdays, and Thursdays from 10:00 a.m. to 3:00 p.m.

Samples may be dropped off at any time during regular business hours, Monday through Friday, from 8:00 a.m. to 5:00 p.m. If you are dropping off a sample outside of in-person assistance hours, please place your sample, completed submission form/referral, and payment in the labeled blue bin located outside Room 206 of Barton Hall on the Durham campus.

For questions, please send an email to email unh.pdl@unh.edu or call 603-862-3043. Thank you for your understanding.
 

Diagnostic Tests Offered:

Regular Diagnosis -  $20
Molecular Diagnosis -  $60
Fungicide Resistance Screening - $60
Pond/Irrigation Water Testing for Phytophthora capsici  - $60


 *Home gardeners may submit plant disease images via the UNH Extension Education Center’s online webform here.
For assistance, call 1-877-398-4769.
 

Soil Testing, Insect/arthropod ID, and Tick Testing services remain fully operational.

 

 

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