Enrichment · Cultural Studies

Spots, powder or wilt?
Start with the likely cause.

A tomato with spotted lower leaves, a squash going white, a cucumber that wilts by noon. Mark twelve symptoms Yes, No or Not sure, and the guide sorts them into six groups, names the likely one and gives the first move gardeners are taught by extension services. Keep a record per plant through the season and see what keeps showing up.

Check a plantWhat you get

Plants checked

The worked example is made up: a tomato, a zucchini and cucumbers from one summer garden. Saved on this device only.

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What you get

Enrichment · Cultural StudiesFree

What you finish with
A record per plant: what and where it is, the kind of plant, where symptoms show, recent weather, how much is affected, twelve symptoms marked Yes, No or Not sure, what you did and whether an expert confirmed it. Names the likely group with its matches and general extension advice; flags a plant more than half affected, too many unsure answers and a likely disease not yet confirmed; counts likely groups across the garden.
Who it is for
Home and school gardeners, community garden members, 4-H and FFA members, and teachers using a garden for science.
Format
Browser reference with a saved record per plant. Prints one plant with the advice, all of them in a table or a blank sheet for the garden; downloads a spreadsheet (.csv); exports and imports a file.
Access
Free. No account, no sign-in and nothing to install. Everything you type stays in this browser; nothing is sent to Caveat.
Where it lives
The Cultural Studies space in Caveat Enrichment.
Support
Questions about access, an order or a correction: team@caveatacademic.com.

How to use it

  1. Look at the top and underside of leaves, the stem and the fruit.
  2. Mark each symptom Yes, No or Not sure.
  3. Read the likely group and its first move.
  4. Take a daylight photo and, for a likely disease, ask your county extension office.
  5. Write what you did, and check again in a week.

Check a plant

Reading the symptoms

Symptom groups at a glanceGroupTell-tale signFirst moveWater mold or blightGreasy patches, fuzz underneathBag it todayVascular wiltWilts on moist soil, stem streaksPull and rotateVirusMottled, twisted new leavesRemove; control aphidsFungal leaf diseasePowder, rings or rust bumpsPrune, dry leavesInsects or mitesHoles, sticky leaves, webbingFind the insectGrowing conditionsLeathery fruit end, crisp edgesWater evenlySymptom groups at a glanceWater mold or blightTell-tale sign: Greasy patches, fuzz underneathFirst move: Bag it todayVascular wiltTell-tale sign: Wilts on moist soil, stem streaksFirst move: Pull and rotateVirusTell-tale sign: Mottled, twisted new leavesFirst move: Remove; control aphidsFungal leaf diseaseTell-tale sign: Powder, rings or rust bumpsFirst move: Prune, dry leavesInsects or mitesTell-tale sign: Holes, sticky leaves, webbingFirst move: Find the insectGrowing conditionsTell-tale sign: Leathery fruit end, crisp edgesFirst move: Water evenly
Two of the six groups are not diseases at all. Checking for insects and watering problems first saves a lot of worry and spray.

Likely is not certain

Many problems look alike. Early blight and Septoria leaf spot both start as spots on lower tomato leaves; a wilt and a root problem both droop. The guide points to the likely group so you know where to start; a plant clinic can confirm it.

The disease triangle

A plant disease needs three things at once: a susceptible plant, the pathogen and the right weather. Most prevention works on the first and third: resistant varieties, spacing for air, watering the soil instead of the leaves, and rotating crops.

Before any spray

Many problems need no spray at all. If you do use one, check that it is labeled for that plant and problem, and follow the label exactly; the label is the law for pesticides in the United States.

Sources

  1. Agrios, G. N. (2005). Plant Pathology (5th ed.). Elsevier Academic Press. (The disease triangle and symptom groups.)
  2. Cornell University, Vegetable MD Online: disease fact sheets for tomatoes and cucurbits (vegetablemdonline.ppath.cornell.edu).
  3. University of Minnesota Extension, Diagnosing plant problems and common vegetable diseases (extension.umn.edu).
  4. National Plant Diagnostic Network (npdn.org) and U.S. Department of Agriculture, Cooperative Extension System: county extension offices.
  5. U.S. Environmental Protection Agency, Pesticide labels: the label is the law (epa.gov).

The worked example is made up. This guide suggests a likely group of causes from what you mark; it is not a diagnosis or a pesticide recommendation. Nothing you type is sent to Caveat. Support: team@caveatacademic.com.