← All guides · Pests · Updated October 2026

Honey fungus on Wingham hedges: four signs, species at risk and the replanting decision.

The RHS calls Armillaria the most destructive fungal disease in UK gardens. In a hedge, it spreads underground via black rhizomorphs, up to about a metre a year. This guide covers how to confirm it, which hedge plants the RHS lists as susceptible, and the decisions you need to make the moment you find it.

Honey fungus covers several species in the Armillaria genus. Some are aggressive and spread actively through the soil to healthy neighbouring plants, while others mainly colonise plants that are already stressed. Either way, the source needs removing or the problem will keep moving through a hedge.

Before treating any fungus as honey fungus, make the bark check described in sign 1 above. Several other toadstools look similar, so toadstools alone are not proof. The RHS describes honey fungus caps as honey-coloured or otherwise brown, in dense clumps, with a whitish collar-like ring below the gills.

1. Where honey fungus tends to start

Honey fungus can occur on any soil. It commonly starts from old tree stumps and root debris, and it takes hold more easily in plants that are already weakened, for example by drought or waterlogging. If several plants in a run fail one after another, look at what stood on that ground before.

Trees inside the conservation area: if the likely source is a tree with a stem over 75mm at 1.5 metres inside the Wingham Conservation Area, Section 211 applies to work on it. A dead tree needs five working days’ written notice to Dover District Council before the work. Hedge plants themselves are normally not covered. See the Section 211 guide.

2. Plants the RHS lists as affected

The RHS lists some plants as particularly susceptible and others as less affected. That helps when deciding what to replant, but the RHS page does not rank every hedging plant, so treat any claim that a species is immune with caution.

Particularly susceptible (RHS list; avoid as replacements in an infected section, and watch existing runs if honey fungus is found nearby):

• Privet (Ligustrum species): listed by the RHS as particularly susceptible.
• Leylandii and thuja (Leyland cypress and Thuja): both on the RHS susceptible list. In a close-spaced conifer screen, root contact can carry the problem along the run.
• Cotoneaster and photinia: both on the RHS susceptible list.
• Forsythia and viburnum: both on the RHS susceptible list.

Less affected (RHS list; a more cautious choice for replanting a cleared section):

• Box (Buxus): listed by the RHS as less affected, though see the box blight guide before planting it.
• Pittosporum: listed by the RHS as less affected.
• Native hedge plants such as hawthorn, blackthorn and hornbeam are not ranked on the RHS page, so there is no firm published resistance rating to rely on.

3. What to do once you have confirmed honey fungus

There are no chemical controls available for honey fungus in garden or hedge settings. All the effective options are physical removal.

Step 1: remove the infected plant and as much root material as possible. The rhizomorphs spread from the root system, not the above-ground growth. Removing the topgrowth alone leaves the problem in place. The RHS advises excavating and destroying all infected root and stump material, by burning or landfill. Follow the main roots outward as far as is practical.

Step 2: check the neighbours. Rhizomorphs can spread up to about a metre a year, so plants either side may already be affected even if they look healthy. Peel back the bark at the base of the nearest ones and look for the white layer and the mushroomy smell.

Step 3: burn or landfill the infected material. Do not compost honey fungus-infected roots, stems or soil. Burn the material on site if that is practical (fire safety first, and check for any local restrictions), or bag it for landfill. Do not use a green waste bin if the local collection goes to composting.

Step 4: consider a barrier. The RHS suggests a buried barrier of butyl liner or heavy plastic, about 45cm deep, to slow rhizomorph spread into healthy ground. Regular deep cultivation of the cleared soil also helps.

Step 5: replant carefully and keep watching. Choose plants from the RHS less-affected list rather than the susceptible list, and check the plants beside the cleared section each autumn for toadstools and each spring for failing growth. Catching a second case early gives you a chance to act before it spreads along the run.

Common questions

How can I tell if my hedge has honey fungus?

Peel back the bark at the base of the suspect plant at ground level. Honey fungus leaves a white, paper-thin fungal layer with a distinct mushroomy smell between the bark and the wood. Black, bootlace-like strands called rhizomorphs may also be visible in the surrounding soil or attached to the roots. In autumn, clusters of honey-coloured toadstools may appear near the stem base. The fourth sign is rapid plant death despite apparently firm roots: if the plant collapses without obvious cause and the roots do not pull out easily, honey fungus is a likely explanation.

Which hedge plants are most at risk from honey fungus in the Wingham area?

The RHS lists privet and Leyland cypress among the particularly susceptible plants, along with thuja, cotoneaster, photinia, forsythia and viburnum. Box and pittosporum are among the less affected plants. The RHS page does not rank every hedging plant, so treat claims that a species is immune with caution.

What can I do once honey fungus is confirmed in a hedge?

There are no chemical controls. Remove the infected plant and as much of the root system as you can, and burn it or send it to landfill rather than composting it. Check the neighbouring plants, as rhizomorphs can spread up to about a metre a year. When replanting, choose plants the RHS lists as less affected. A buried barrier of butyl liner or heavy plastic, about 45cm deep, can slow spread.

When can I legally carry out the removal work in Wingham?

The Wildlife and Countryside Act 1981 protects wild birds and nests that are in use or being built, but sets no calendar dates; 1 March to 31 August is the accepted guidance window. Heavy digging and clearance work is best planned for September to the end of February. A visibly dead plant with desiccated foliage poses no nesting risk. If removal is needed within the guidance window, check the surrounding hedge for active nests first.

Does a Section 211 notice apply if I need to remove infected plants near the Wingham Conservation Area?

Section 211 applies to trees, not normally to hedge plants or shrubs. A tree with a stem over 75mm at 1.5 metres inside the Wingham Conservation Area needs six weeks’ written notice to Dover District Council, and a dead tree needs five working days’ notice. Most privet or leylandii hedge plants will not reach that size. If the honey fungus involves a larger tree, measure the stem before any work. See the Section 211 guide.

Sources: RHS, Honey fungus (checked 12 October 2026); Wildlife and Countryside Act 1981 s.1; GOV.UK, Tree Preservation Orders and trees in conservation areas.