Plant Disease & Diagnosis Services

diseased leaf

Update (7/14/20):

The soils lab is not currently open, but we recommend growers still take tissue samples at the recommended time for the specific crop (typically between July 15 and 30), and hold it until the soil processing lab reopens. Clean, dried leaves should be held in a dry area in an open paper bag until we are accepting samples. It is best to hold the sample at your farm until we reopen, which we expect to be in early fall. Please do NOT mail in the sample until our reopening is official. For more information on leaf tissue testing please visit the NH Vegetable & Fruit News blog post here.

The Food and Agriculture team wants to let you know that we are still working and available to provide guidance and help during this busy season.  While face-to-face meetings and in-person programming have been curtailed, we are still working every day to help your season be a successful one. Watch for our newsletter or visit our website to get updates on upcoming programs and newly available resources.

Walk-in and mail-in samples cannot be accepted for any diagnostic service until further notice.

For home gardeners:

Please contact us at or 1-877-EXT-GROW (398-4769), photos are welcome and may help us identify any weed, disease, or insect problems you encounter.  In the absence of a soil test, home gardeners are encouraged to follow guidelines recommended in our factsheets. If you have misplaced your old soil test results, contact Soils already submitted to the UNH lab will be processed when services resume.

For commercial producers/operations only:

We are very much available to talk via phone, email, or ‘virtual’ visits.  We can even make physical site visits, as long as we’re able to follow certain protocols. While we are not able to process soil samples at this time, some soil testing laboratories in nearby states are still processing; commercial growers in need of a soil test may want to consider sending samples to one of these labs. We do recommend that you make sure that they are still receiving samples prior to sending samples.

University of Maine Analytical Lab

Pennsylvania State University Soil Testing Lab

University of Connecticut Soil Nutrient Analysis Lab

  • Plant samples: 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.
  • Arthropod samples: Our staff are accepting digital samples sent by email to Submission must include your name, phone number, business name, county, where you found the specimen 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.