Plant Diagnostic Lab

  • close-up of plant leaf

The UNH Plant Diagnostic Lab is accepting samples!

Reach out with any questions to or 603-862-3043. 

Please note: 

  • We can only accept in-state samples at this time.    
  • No Hemp or Cannabis samples at this time 
  • If you are interested in a particular molecular test, please contact the lab first to see if it is available. 
  • Expect 7-10 business days for results.  Reports will be emailed to the address provided on the form.  Be sure to check your spam folder for the report and call/email with any questions! 

Each sample must include a sample submission form and the $20 sample fee. 

Download Sample Submission Form

Getting Your Samples to Us

UNH Plant Diagnostic Lab
Barton Hall
34 Sage Way
Durham, NH 03824

Drop Off

Barton Hall is open to the public daily from 8 a.m. - 5 p.m. Monday-Friday.  Follow the signs & head upstairs to Barton 206.  You may leave your plant sample with a form with anyone in the lab OR leave it in the blue sample drop off boxes outside of the lab door. 

 Do not drop off plant samples in the soil drop off box outside of Barton Hall.  We are unable to process plants samples from that box because they degrade too quickly. 

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  • Extension State Specialist, Plant Pathology
    Director of the UNH Plant Diagnostic Lab and State Extension Specialist
    Phone: (603) 862-0051
  • Plant Diagnostic Laboratory Technician
  • Plant Diagnostic Laboratory Technician