How to diagnose garden plant, tree and houseplant problems
“What is wrong with my plant?” “What can I do to save my tree?”
Every week our Master Gardener call office receives questions similar to these. If it's an emailed question, there's usually a photo of a sad looking plant or tree attached.
This week's column goes through questions asked to get a good diagnosis of plant problems when folks send us sad plant photos. They include all the information we need to provide a proper diagnosis. This may also help you become better at determining what is wrong with your plants.
The first step to diagnosis is to examine all parts of the plant: Leaves, stems, bark and roots if possible.
Next, do your best to answer the following 20 questions about a sick plant, shrub or tree.
What kind of plant is it? Good plant identification is important.
How does a healthy plant of this variety/type look? This is important because with some plant there are varieties that normally have yellow new leaves or mottled leaves.
Are there common problems for this plant? What diseases is the plant known to get, such as peach leaf curl on peaches.
What do you see that looks abnormal? Is the plant wilting? Are there discolored leaves?
What is the overall health of the plant? Is it only part of the plant that is sick or is the entire plant affected?
What signs or symptoms do you see? Symptoms describe damage to plant tissues, and signs are evidence of the plant pathogen, pest or pest residue such as fungal spores or aphid honeydew.
Are there other sick plants surrounding it?
Where is it situated? On the west side of a house? Along a driveway? In a fenced garden?
Who knows about the plants? Does someone specific care for the plants?
When did the symptoms first appear? How long have the symptoms been there?
What is the plant's history? Was it recently planted? Where did it come from?
What is the site's history? Is the site known to be really wet? Is it colder than surrounding areas?
What does the owner of the plant think the problem is? Was there something they might have done to cause the problem?
What diagnostic tools might be useful for diagnosis? Think of websites like Plant ID, Purdue Tree Doctor and the UC IPM Diagnostic Tool.
What additional resources are available, like a soil test or plant sample test?
Is there a sample that you can take that would help with the diagnosis; For example, a leaf to look at under a microscope or send off for a tissue sample?
What is your best diagnosis as to what is wrong with the plant or tree?
Do you still need additional information to confirm your diagnosis?
Is this a significant problem for the plant or is it something that will go away on its own?
Do you have recommendations for correcting the problem, eradicating the pest or curing the disease?
With a proper diagnosis, the University of California Integrated Pest Management website has pest notes that provide detailed strategies for managing each disease or pest. Go to bit.ly/3ZO49tx or bit.ly/3TiK78k.
The Shasta Master Gardeners Program can be reached by phone at 530-242-2219 or email mastergardener@shastacollege.edu. The gardener office is staffed by volunteers trained by the University of California to answer gardeners' questions using information based on scientific research.
This article originally appeared on Redding Record Searchlight: How to diagnose garden plant, tree and houseplant problems
