GrowingHQ
Physiological disorderLeavesWhole plantFlowers

Underwatering

Easier to correct than overwatering and easily confused with it, because a plant short of water and a plant drowning both wilt. The distinguishing observation is not the plant at all — it is the compost, and it takes two seconds to check.

What brings it on

Long gaps between waterings, a pot too small for the plant, a peat-based compost that has dried to the point where water runs down the sides instead of soaking in, hot or windy weather, or a plant that has become pot-bound and has more root than compost.

source

Sourced guidancehigh confidence

  • Royal Horticultural Society: Watering

Checked 2026-08-13

Preventing it

Ordered by how much difference each measure actually makes, not by how often it is repeated.

  • Water thoroughly rather than frequently: enough that it runs from the bottom of the pot, then not again until the compost has dried to the appropriate depth for that plant. Little and often wets the surface and leaves the root ball dry.
    source

    Sourced guidancehigh confidence

    • Royal Horticultural Society: Watering

    Checked 2026-08-13

Dealing with it once it is there

  • Stand the pot in a bowl of water for half an hour so the compost rewets from below. Compost that has dried out completely repels water from above, and a can poured over the top runs straight down the gap at the side and out of the bottom, leaving the root ball as dry as it was.
    source

    Sourced guidancehigh confidence

    • Royal Horticultural Society: Rewetting dry compost

    Checked 2026-08-13

Signs that lead here

Each of these lists the other things that produce the same sign, and how to tell them apart.

On sprays and treatments

GrowingHQ does not tell anyone what to apply, at what rate, or how often. Pesticide approvals differ by country, change without notice, and the product label is legally binding — it is also the document you are holding. What is described here is cultural and physical control, which is what a home grower can act on without a label in front of them.

Plant-specific guides

Where this is one of several causes that look alike on a particular plant, GrowingHQ publishes the differential rather than the general answer.