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Florist's cyclamen spots on leaves: causes and what to do

8 results in the diagnosis tree begin with spots on the leaves, 5 of them marked likely when the answers fit. They are ordered here for Florist's cyclamen (Cyclamen persicum), using what its sources say about light, soil moisture, humidity and pests and diseases and 2 problems recorded for it.

Sources last read 14 September 2026.

Start the diagnosis for this Florist's cyclamen

Florist's cyclamen (Cyclamen persicum), the whole plant.
Magnus Manske, CC BY-SA 3.0 · Wikimedia Commons

Cyclamen persicum, the Persian cyclamen, is a species of flowering herbaceous perennial plant growing from a tuber, native to rocky hillsides, shrubland, and woodland up to 1,200 m (3,900 ft) above sea level, from south-central Turkey to the Levant. Cultivars of this species are the commonly seen florist's cyclamen. Wikipedia, CC BY-SA 4.0

Native range: Algeria to E. Medit. (subtropical). Also sold as Persian Cyclamen.

What Florist's cyclamen’s sources say that bears on this

Light
Full sun, Partial shade
RHS · read 13 September 2026
Soil moisture
Well-drained
RHS · read 13 September 2026
Humidity
ASHRAE recommends indoor relative humidity between 30% and 60%
Penn State Extension · read 13 September 2026
Pests and diseases
Can be troubled by squirrels and mice, and by vine weevil when in containers. Diseases: black root rot and cyclamen grey mould.
RHS · read 13 September 2026

How this shows up on a Florist's cyclamen

Soft patches that grow a gray fur: botrytis

Patches of the florist's cyclamen turn soft and collapse under a gray, velvety coating.

RHS lists gray mold among the diseases it may get. It thrives on spent flowers and fallen leaves left on the plant, and moves from there to living tissue.

Telling it apart: The texture. Tissue under gray mold is soft and rotting; sun scorch is dry.

RHS · read 13 September 2026

Washed-out patches that do not spread to the shaded side

Upper surfaces lose colour while the undersides stay green, and nothing below the top of the plant is touched.

Sun through a window on a still day heats a leaf far above the air around it. Its source describes full sun, partial shade; the glass adds the heat that does the damage.

Telling it apart: Whether the patches grow. Scorch is done once it happens; a leaf spot keeps spreading.

RHS · read 13 September 2026

Possible causes, likeliest first for a Florist's cyclamen

  1. Most likely spider mites

    Why: Spider mites feed on individual leaf cells, and each emptied cell shows as a pale speck.

    What to try:

    • Move the florist's cyclamen away from other plants.
    • Wash the leaves, top and underside, with a strong spray of water in a shower or sink.

    What would settle it: Hold a sheet of white paper under a leaf and tap the leaf. Tiny specks that move across the paper are mites.

    Check this with the questions

  2. Most likely powdery mildew

    Why: A white coating that wipes off is the surface growth of a fungus.

    What to try:

    • Remove the worst-affected leaves.
    • Improve air movement around the florist's cyclamen and space it away from others.

    What would settle it: Wipe a patch. Powdery mildew comes away and leaves a yellowed patch beneath. White that does not wipe off is part of the leaf, or a mineral deposit from hard water.

    Check this with the questions

  3. Most likely thrips

    Why: Thrips rasp the leaf surface and drink what leaks out, which leaves silvery, papery streaks.

    What to try:

    • Move the florist's cyclamen away from other plants.
    • Wash the leaves thoroughly and remove badly damaged ones.

    What would settle it: Tap a leaf over white paper. Thrips are slender, fast-moving and about the size of a comma; they are easy to see once they are on paper.

    Check this with the questions

Less likely for a Florist's cyclamen, still possible

Questions

What usually causes spots on the leaves on a Florist's cyclamen?
For Florist's cyclamen: spider mites, powdery mildew and thrips.
How can I tell which one it is on my Florist's cyclamen?
What do the marks look like? Pale, dry, bleached patches on the side facing the window; Brown or black spots, many with a yellow ring around them; Tiny pale speckles all over, sometimes with fine webbing underneath; A white powdery coating that wipes off; Silvery streaks with tiny black dots; Dark, soft, water-soaked patches.
What do Florist's cyclamen's sources say about its light?
RHS: Full sun, Partial shade.
What does this look like on a Florist's cyclamen?
Patches of the florist's cyclamen turn soft and collapse under a gray, velvety coating. Telling it apart: The texture. Tissue under gray mold is soft and rotting; sun scorch is dry.
Is Florist's cyclamen safe to handle while I check it?
Its sources list it as toxic to cats and dogs. Wash your hands after handling the roots or sap, and keep trimmings away from pets.

Something else wrong with the Florist's cyclamen?

Everything the sources say about Florist's cyclamen

What this does not cover

This page orders a decision tree's results using a plant's sourced care. It has not seen your plant, its pot or its window, and two problems at once are common: that is the usual reason a confident answer turns out wrong. The questions in the diagnosis tool narrow it further than a list can.