Plant Diagnostic Lab

  • close-up of plant leaf

Important Notice

The University of New Hampshire Plant Diagnostic Lab has temporarily suspended its services for the remainder of 2025. We apologize for any disruptions caused by this temporary closure and will provide updates on its reopening as soon as possible.  

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

 

If you submitted a plant diagnostic sample before August 7, and have questions, please contact us at 603-862-0509 or soil.testing@unh.edu.

For samples submitted after August 7, please note:

  • Home gardener samples will be returned by mail to the address provided on the submission form, along with any payment included.
  • Commercial growers or businesses will be contacted directly to determine the best way to return materials and discuss alternative options. While the lab is closed, we recommend using the University of Maine Plant Disease Diagnostic Lab services.
     
  • Home gardeners may submit plant disease images via the UNH Extension Education Center’s online webform. 
    For assistance, call 1-877-398-4769.

For any questions related to plant diagnostic samples, contact us at 603-862-0509 or soil.testing@unh.edu.

 

 

 

 

 

 

 

 

 

 

 

How to Package Submissions to the UNH Plant Diagnostics Lab

Articles

Tyler Edwards in lab
Welcome Tyler Edwards
Tyler Edwards Joins Extension as the Plant Pathology Program Manager
UNH Extension is pleased to announce the hire of Tyler Edwards as the Plant Pathology Program Manager. Learn More
UNH Extension Can Help You Diagnose Plant Problems
UNH Extension Can Help You Diagnose Plant Problems
What do you do when you encounter a plant problem such as disease or abnormal growth in the landscape? You or a client may find a problem occurring w... Learn More
Bo Liu portrait
Welcome Bo Liu
Bo Liu, Ph.D., joins UNH Extension as the Director of the UNH Plant Diagnostic Lab and State Extension Specialist
UNH Extension is pleased to welcome Bo Liu, Ph.D., as our Plant Diagnostic Lab Director and State Specialist. Learn More

Events

Resources

Frogeye leaf spot and black rot and on Apple
Frogeye leaf spot and black rot on Apple
Frogeye leaf spot and black rot caused by the fungus Botryosphaeria obtuse (Schwein) is an economically important disease of apple in the Northern and... Learn More
Gibbera twig blight shows black spots, stromata, with red margins
Gibbera twig blight
Gibbera twig blight is known to affect blueberries in Merrimack, Sullivan, Cheshire and Grafton counties of New Hampshire. This disease will affect fr... Learn More
Black growth on hellebore plant
Black Death of Hellebore
Black death of hellebore, a virus disease affecting hellebores in nursery and home gardens, was found in a nursery in Grafton County, New Hampshire, i... Learn More
Leaf rust spots on the underside of blueberry leaves; spots have a distinct brown edge with typical yellowish orange rust pustules
Blueberry Leaf Rust
In the summer and fall of 2023, blueberry leaf rust was found widely distributed in New Hampshire, including Merrimack, Hillsborough and Strafford cou... Learn More
Exobasidium fruit spot on harvested blueberries
Exobasidium leaf and fruit spot of blueberry
Exobasidium leaf and fruit spot of blueberry is a fungal disease affecting both leaves and berries. Symptoms matching this disease were reported in se... Learn More
Yellow and green leaves with brown spots
Cherry Leaf Spot
Leaf spot is one of the important fungal diseases on cherry trees in the United States. The disease mainly affects the leaves; the pathogen will cause... Learn More

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