GrowingHQ
Leaves

Crisp brown edges around the leaf margin

A band of dry, brittle brown tissue following the outline of the leaf, usually with a sharp boundary against healthy green. It is the part of the leaf furthest from the water supply, so almost anything that interrupts that supply shows here first — which is why the margin itself tells you little and the context tells you everything.

What causes it, and how to tell them apart

Work down the list making the observation under each heading. GrowingHQ will not guess which one you have — the observation is the answer.

  1. Dry airvery common
    source

    Sourced guidancehigh confidence

    • Royal Horticultural Society: Houseplant problems

    Checked 2026-08-13

    How to tell

    The compost is moist and the room is heated. Affects thin-leaved tropical plants first, and worsens in winter when indoor humidity falls.

    source

    Horticultural consensusmoderate confidence

    No external citation — see the evidence type above.

    Checked 2026-08-13

    If it is this, do first

    Group plants together or stand the pot on a tray of damp gravel, and move it away from radiators.

    source

    Sourced guidancemoderate confidence

    • Royal Horticultural Society: Houseplant problems

    Checked 2026-08-13

  2. Fertiliser scorchcommon
    source

    Sourced guidancemoderate confidence

    • Royal Horticultural Society: Fertiliser damage

    Checked 2026-08-13

    How to tell

    A white crust on the compost surface or around the pot rim, and a history of regular feeding — particularly feeding at more than the label rate or onto dry compost.

    source

    Horticultural consensusmoderate confidence

    No external citation — see the evidence type above.

    Checked 2026-08-13

    If it is this, do first

    Stop feeding and flush the pot through with plenty of clean water, letting it drain away freely to carry the salts out.

    source

    Sourced guidancemoderate confidence

    • Royal Horticultural Society: Fertiliser damage — recovery

    Checked 2026-08-13

  3. Potassium deficiencyoccasional
    source

    Sourced guidancemoderate confidence

    • Royal Horticultural Society: Potassium deficiency

    Checked 2026-08-13

    How to tell

    Scorching on the OLDEST leaves first while new growth stays clean, on a long-cropping or heavily fruiting plant, often with poor fruit colour.

    source

    Horticultural consensusmoderate confidence

    No external citation — see the evidence type above.

    Checked 2026-08-13

    If it is this, do first

    Feed with a fertiliser formulated for fruiting at the rate on its label, and judge the result by the new leaves rather than the damaged ones.

    source

    Sourced guidancemoderate confidence

    • Royal Horticultural Society: Potassium deficiency — treatment

    Checked 2026-08-13

  4. Draught stressoccasional
    source

    Sourced guidancemoderate confidence

    • Royal Horticultural Society: Houseplants — siting

    Checked 2026-08-13

    How to tell

    Damage concentrated on the side of the plant facing a door, an opening window or a radiator, rather than distributed evenly.

    source

    Horticultural consensusmoderate confidence

    No external citation — see the evidence type above.

    Checked 2026-08-13

    If it is this, do first

    Move the plant a metre further into the room, away from the moving air.

    source

    Sourced guidancemoderate confidence

    • Royal Horticultural Society: Houseplants — siting

    Checked 2026-08-13

  5. Underwateringcommon
    source

    Sourced guidancehigh confidence

    • Royal Horticultural Society: Watering houseplants

    Checked 2026-08-13

    How to tell

    The compost is dry to a finger pushed in deeply, the pot is light to lift, and the whole plant is limp as well as brown at the edges.

    source

    Horticultural consensusmoderate confidence

    No external citation — see the evidence type above.

    Checked 2026-08-13

    If it is this, do first

    Water thoroughly until it runs from the base. If the water runs straight through without wetting the compost, stand the pot in water instead.

    source

    Sourced guidancehigh confidence

    • Royal Horticultural Society: Watering houseplants

    Checked 2026-08-13

Where GrowingHQ holds more for one plant

This page lists the causes across every plant. The plants below are the ones where something about that plant changes the answer — different candidates, or a different observation that separates them.

Ornamentals

Commonly reported on