Join the RHS today and support our charity
Free personalised gardening advice
RHS members get reduced ticket prices
RHS members get free access to RHS Gardens
Reduced prices on RHS Garden courses and workshops
020 3176 5800
Mon – Fri | 9am – 5pm
Help us achieve our goals
Make a donation
I have forgotten my password
Keep me signed in
Register for free to receive our newsletters, add comments to blogs/articles and to save content.
See what events are on near you and browse your bookmarked pages.
Coral spot is a fungal disease of woody plants causing branches to die back. Small coral-pink raised spots (pustules) form after the branch dies. Coral spot often indicates that the plant has been weakened by other factors.
Coral spot, so-called because after affected branches die they develop pinhead-sized coral-pink fungal pustules, is a disease caused by the fungus Nectria cinnabarina. It causes die-back of branches of woody plants, but the causal fungus is a weak pathogen and its presence often indicates that the plant also has other problems.
Among broadleaf trees and shrubs, Acer, Aesculus (horse chestnut), Carpinus (hornbeam), Fagus (beech), Juglans (walnut) and Tilia (lime) are among the more susceptible to attack. It is rarely found on conifers.
The small coral-pink fungal pustules may be seen at all times of year.
You may see the following symptoms:
Always prune in dry weather. When carrying out routine pruning, cut branches through the collar (ring of slight swelling found at the base of branches). Healing of wounds occurs most quickly here, compared to leaving stubs (snags) or cutting flush with the bough or trunk. If die-back occurs after pruning, remove dead material to avoid further infection.
Prune out infections promptly and cut back to healthy wood. Do not leave dead wood to moulder and generate spores in damp corners of the garden.
There are no specific fungicidal controls for this disease.
If it is necessary to prune in wet weather when risks of infection are high, or if the plant has previously shown a particular susceptibility to the problem, use a wound paint (Vitax Medo, Bayer Garden Arbrex Seal and Heal, Growing Success Prune and Seal) to protect the cut.
However, wound paints are not recommended for routine use as they are thought to interfere with healing and may even provide a better environment for rots.
The causal fungus is very commonly found growing as a saprophyte (a term describing a fungus that feeds on dead organic material) on dead wood, especially old hazel peasticks. Spores from the pink pustules on the bark are dispersed in rain splash and wind-blown rain.
Spores can infect trees in a number of ways:
Although dead wood is colonised initially the fungus can then move on into living wood to cause die-back. After death, the fungus grows out of the dead bark to form the characteristic small pink pustules that produce the spores.
Apple cankerBacterial cankerBracket fungiDisposing of diseased materialHedges: pruning timesHedges: renovationTrees: pruningWhy has my tree or shrub died?Willow anthracnose, scab and canker
the RHS today and get 12 months for the price of 9
RHS members can get exclusive individual advice from the RHS Gardening Advice team.
Register for the site or sign in to share your experiences on this topic and seek advice from our community of gardeners.
We're a UK charity established to share the best in gardening. We want to enrich everyone's life through plants, and make the UK a greener and more beautiful place.
Join the RHS today and get 12 months for the price of 9