Why Does My Currant Bush Have Orange Spots on Dead Wood?

Clusters of small, vivid salmon-pink or orange pustules on dead or dying wood on a currant bush are one of the most visually distinctive fungal signs in the garden. The culprit is coral spot (Nectria cinnabarina), a common woodland and garden fungus that lives as a harmless decomposer on truly dead wood but can become a pathogen when it encounters weakened or recently killed tissue on a living plant. Once established on dead stubs or old pruning wounds, it can spread into adjacent healthy stems and cause progressive dieback.

How coral spot behaves on currants

Nectria cinnabarina produces two types of fruiting bodies — the salmon-pink pustules (conidial stage, common in summer) and darker, rougher structures (perithecia, the sexual stage, appearing in autumn). Both release spores that infect through wounds on the plant. The fungus is not primarily a pathogen of healthy tissue — it needs a dead or severely weakened entry point to gain a foothold. On currant bushes the most common entry sites are stubs left when branches were cut too far from the main stem, dead wood left on the plant after frost or dieback, and large pruning wounds left unsealed.

Identifying an active versus a passive infection

Coral spot visible only on clearly dead, dry wood that is already fully detached from the live part of the plant is relatively benign — the fungus is doing its natural job of breaking down dead wood. The concern is when orange pustules are present on wood that is attached to the living framework and the dieback is progressing downward into stems that still carry healthy growth above. If you can trace the brown, discoloured wood under the bark continuously from a dead section down into living tissue below the orange pustules, the fungus is actively killing the branch and needs to be removed urgently.

Removing affected wood

Cut back all affected tissue to healthy, clean white wood, making the cut at a collar or node rather than midway along an internode. Remove the cut material from the garden immediately — do not leave it on the soil surface or in the compost heap, as the pustules continue to release spores after cutting. Sterilise your pruning saw or loppers between each cut using a 10% bleach solution or a proprietary disinfectant spray — recontamination via tools is a common reason coral spot appears on multiple stems within days of pruning. Apply wound sealant to cuts larger than about a centimetre to reduce new infection risks.

Preventing recurrence

Coral spot is an opportunist that exploits poor pruning practice more than any other single factor. Always cut back to a live bud or branch collar with no stub remaining — a stub dries out, dies, and becomes an immediate habitat for the fungus. Prune during dry weather when wounds dry quickly, reducing the window for spore germination. Keep tools sharp so cuts are clean rather than ragged. Apply wound paint to any cut larger than about 1cm, especially on older framework wood where the bark is thick and healing is slower.

Removing old dead stubs

Inspect your currant bushes during winter or early spring for old pruning stubs — sections of dead branch left projecting from the framework from previous years. These are prime habitat for coral spot even when no orange pustules are currently visible. Cut them back to the live collar with a sharp saw, treat the wound, and dispose of the material off-site. A single annual inspection for dead stubs takes only minutes and significantly reduces the standing dead wood that allows coral spot to establish.