Sample Submission Guidelines:


General Plant Disease Identification: Test fees waived for in-state / $20 for out-of-state

  1. Examine all plant parts and determine the parts which you believe to be diseased (remember that diseased roots can cause wilted leaves). Ideally the whole plant should be sent when possible.
  2. Place root ball in a plastic bag with some soil and tie it so the soil doesn’t contaminate the foliage. Wrap the plant in a barely damp paper towel or newspaper and place the entire plant in a sealed plastic bag.
  3. If the plant is too large to make the above possible:
    • Place fresh leaves in a sealed plastic bag that include healthy and symptomatic leaves.
    • Place cut stems in another sealed plastic bag.
    • Shake roots free of soil, wrap in a barely damp paper towel and place in plastic bag.
  4. Please mark sample packages with “Warning” if sample has thorns or spines.
  5. Samples should be packaged and sent as quickly as possible. If the sample cannot be sent the same day, it should be kept refrigerated as to limit the sample from degrading.
  6. When sending samples through the mail, try to mail early in the week so samples will not sit over the weekend.
  7. All samples must be sent with a completed Plant Disease Submission Form (PDF). Provide complete information on the form and keep the form separate from the sample. Limit sample information to one (1) sample per form and indicate which form goes with each sample. You are encouraged to include any other pertinent information in addition to that on the form.
  8. Currently no physical cannabis samples can be received by the lab unless it is considered hemp, and an accompanied hemp license number is provided on the submission form. The Plant Disease Diagnostic Lab does not provide virus or viroid testing on cannabis.
  9. Please expect 5-10 business days after sample arrival for diagnosis. A report detailing the diagnosis and management recommendations will be sent via email (if provided) for each sample. The subject title of this report will read “Final Report: Final Report for Sample ########”. Please check your spam folder if you suspect you have not received this report and select “Not Spam” so that future reports will go into your inbox. Most spam folders self-delete following 30 days; if this is the case and you cannot find your report, please contact us to resend it.
Example of packaged garlic samples to send to our plant disease diagnostic lab.
Example of Plant Submission(Completion of Step 2)

Garlic Bloat Nematode Testing: $20 fee per sample for in-­state, and $50 for out-­of­-state samples.

Plant Samples:

  • Collect five entire living plants between June 15th and July 30th in varying stages of decline.
  • Do not submit totally dead plants; try to send weak or stunted plants starting to decline.
  • If garlic is planted in multiple fields separated by 100 feet or more, each field requires a separate sample.
  • Cut the tops off the garlic, leaving the bulb and about a foot of above­-ground plant.
  • Wrap the five bulbs in dry newspaper and place the newspaper in a sealed plastic bag.
  • Keep the sample cool until shipping, which should be done at the beginning of the week.
  • Complete the Plant Disease Diagnostic Submission Form and include it with the sample.
  • Limit sample information to one (1) sample per form and indicate which form goes with each sample.

Soil Samples:

  • Please note that soil testing will only identify Ditylenchus dipsaci, the pathogenic nematode that causes Garlic Bloat, not White Rot or Botrytis.
  • Collect about a cup of soil from under and around garlic plants in varying stages of decline after July 1st.
  • If garlic is planted in multiple fields separated by 100 feet or more, each field requires a separate sample.
  • Place the soil in a sealed plastic bag.
  • Keep the sample cool until shipping and ship early in the week.
  • Complete the Plant Disease Submission Form (PDF) and include it with the sample.