Diagnosing plants - getting started: Key Learnings

One of the most often requested services of a Master Gardener is to diagnose a plant problem.  

We're not allowed to make house calls, so you need to bring your plant problem to us at a Master Gardener clinic.  Plant diagnosis is challenging enough, but the challenge becomes bigger when the owner of the problem brings an inappropriate sample. 

So..... to help us help you, here are some pointers on what makes a good sample:

1.  FRESH IS BEST
Bring us a fresh, live sample. The freshest you can get is the rule. Trim off the offending problem right before you come to see us.

2.  THE GOOD, BAD AND THE UGLY
Bring us a sample that includes a healthy portion of the plant AND a sick/diseased part AND a dying/dead part (if it's progressed that far).  But don't bring in a totally dead plant.  We can't help you if it's totally toast. 

3.  BE GENEROUS
Bring us a sample that includes as much of the plant's features as you can:  leaves, stem, branch, bud, flower, seeds.  Obviously if it's a small plant, you may not be able to bring us a sizeable sample, but do the best you can.  If you're bringing us a weed, bring us the entire plant - roots and all.

4.  WRAP IT RIGHT
Don't put it in a plastic bag.  It needs to "breathe", so carefully wrap it in a paper towel or newspaper or a paper bag, and be sure not to squash it. 

5. TELL US WHAT IT IS
Family, genus, species, cultivar, hybrid....as much as you know.   If you still have the plant label bring that with you - that's the ideal! If you don't know the name of the plant that's OK, we'll find out for you, but it speeds things up if you already have the full details.

6.  PICTURES ARE WORTH A THOUSAND WORDS
Bring us some photos:  of the problem plant, the bed it's planted in (so we can see what other plants it hangs out with), and a good scenic shot of the general landscape (so we can better understand the environment it's living in).  All of these may be clues as to what's causing the problem.

7.  HISTORY LESSON
Be prepared to tell us as much about the plant as you know.

• When was it planted?
• How was it planted?
• What's the soil like that it's planted in?
• Is it mulched in?
• How do you water/feed/fertilize it?
• Have you ever treated it with chemicals?  If so, what and when?
• What other chemicals do you use in your landscape?
• Any unusual things going on around your house (construction, tree felling, installed hardscape/sprinklers etc)

7.  DEAD BUGS ONLY PLEASE!
If you think you know the culprit causing the problem and want to bring us a sample to see, be sure it's dead first!   For bugs, the best way to do this without damaging it is to put the larvae/maggot, nympth or mature insect in a small plastic container and put the sealed container in the freezer to finish things off.  Then gently cover the dead bug with a facial tissue or paper towel to stop it rattling around in the container while in transit.

8.  SAMPLE NO-NOs

• No single leaves, twigs, flowers, stems etc.
• No dead plant specimens.
• Don't tape it, twist tie it, bundle it up in twine or in any way bind it together.
• No plastic bags or containers (for plant samples)
• No house pests, pet pests or people pests - we only diagnose garden/plant pests.

If we can't diagnose your problem at the clinic, we'll happily pack it up and send your sample to the lab for proper diagnosis.  When the problem's been identified, you'll be notified in writing, and your clinic will be copied on the results so we can learn from the experience and be better equipped to handle the next client with a similar problem.