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English lavender 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 English lavender (Lavandula angustifolia), 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 English lavender

English lavender (Lavandula angustifolia), the whole plant.
Dieringer63, CC BY-SA 4.0 · Wikimedia Commons

Lavandula angustifolia, formerly L. officinalis, is a flowering plant in the family Lamiaceae, native to the Mediterranean basin. Wikipedia, CC BY-SA 4.0

Native range: NE. Spain to Italy (temperate). Also sold as common lavender, English Lavendar, Lavender, Narrow-Leaved Lavender and spike-oil plant.

What English lavender’s sources say that bears on this

Light
Full sun
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 cuckoo spit (froghoppers) and rosemary beetle. Diseases: a high-risk host of Xylella fastidiosa; grey moulds (Botrytis) and, rarely, honey fungus can occur.
RHS · read 13 September 2026

How this shows up on an English lavender

Dry scorched spots after a move into a sunnier spot

On an English lavender the marks are patchy and one-sided. Leaves on the shaded side of the plant keep their colour entirely.

Glass concentrates what would be tolerable outdoors, because it holds the heat and removes the moving air that carried it away. Its source describes full sun.

Telling it apart: Whether it followed a move or a season. Scorch appears within days of a change in position.

RHS · read 13 September 2026

Gray, furry patches on damaged or dying leaves

Damaged or dying tissue on the English lavender is covered in gray, fuzzy growth, and the rot spreads into healthy parts.

RHS lists gray mold among the diseases it may get. Crowding and damp air around the plant let spores settle and grow.

Telling it apart: The fur. Gray mold carries a gray, dusty coat; a plain leaf spot does not.

RHS · read 13 September 2026

Possible causes, likeliest first for an English lavender

  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 english lavender 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 english lavender 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 english lavender 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 an English lavender, still possible

Questions

What usually causes spots on the leaves on an English lavender?
For English lavender: spider mites, powdery mildew and thrips.
How can I tell which one it is on my English lavender?
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 English lavender's sources say about its light?
RHS: Full sun.
What does this look like on an English lavender?
On an English lavender the marks are patchy and one-sided. Leaves on the shaded side of the plant keep their colour entirely. Telling it apart: Whether it followed a move or a season. Scorch appears within days of a change in position.

Something else wrong with the English lavender?

Everything the sources say about English lavender

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.