GrowingHQ
DiseaseStemsLeavesWhole plant

Clematis wilt

A shoot or a whole large-flowered clematis collapsing over a day or two, usually just as the buds are about to open, with a dark shrunken lesion at a node low on the stem and roots that are entirely sound. That combination — dead top, live roots — is the identification, and it is also the reason the plant is usually not lost: cut back below the lesion into the buried crown and it commonly regrows.

Caused by: Calophoma clematidina · also called clematis dieback, clematis collapse, sudden clematis wilt

What brings it on

Almost entirely a disease of the large-flowered hybrids; the vigorous small-flowered species groups are rarely affected. It enters through damage at a node — a stem snapped by wind or by handling — which is why deep planting and a supported, undamaged stem base matter more than any spray.

source

Sourced guidancehigh confidence

  • Royal Horticultural Society: Clematis wilt
  • Plant Finder — Missouri Botanical Garden: Clematis — problems

Checked 2026-08-13

Usually seen: May, June, July

Preventing it

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

  • Plant large-flowered clematis with the crown 8–10cm below the soil surface. Buried buds are what allow a plant to rebuild after a collapse, and they are the reason the same shrub that 'died' in June is back the following spring.
    source

    Sourced guidancehigh confidence

    • Royal Horticultural Society: Clematis — planting

    Checked 2026-08-13

  • Tie in new growth as it extends rather than letting it whip about, since the wounds the fungus enters through are mostly mechanical.
    source

    Horticultural consensusmoderate confidence

    • Plant Finder — Missouri Botanical Garden: Clematis culture

    Checked 2026-08-13

Dealing with it once it is there

  • Cut the affected stems out below the lesion, down to healthy tissue or to ground level, and remove the prunings. Keep the plant watered and it will usually shoot again from below ground within the same season or the next.
    source

    Sourced guidancehigh confidence

    • Royal Horticultural Society: Clematis wilt — control

    Checked 2026-08-13

Widely repeated, and not supported

Recorded so GrowingHQ can address them. These are not alternative approaches — they are things the evidence does not back.

  • “A clematis that has collapsed is dead and should be dug out.”

    Deep-planted large-flowered clematis regrow from buried buds often enough that digging one out in the first season is usually premature. Cut it back, water it, and give it until the following spring.

    Sourced guidanceCommonly said, not supportedhigh confidence
    • Royal Horticultural Society: Clematis wilt — control

    Checked 2026-08-13

What it affects

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.