Buxus Diseases

Buxus (also know as Boxwood) is one of the most popular plants in the English gardens. They look beautiful shaped as a ball or small hedge. Unfortunately, they are not disease free.

The most common disease that we hear about is Box Blight, but that that is not the only type of disease that Buxus are susceptible to. Warm, wet weather helps fungus diseases to take over our gardens but lets have a look at the other common buxus problems as well.

Fungus diseases

Buxus Blight

The characteristic black spots on the leaf appear usually in April/May, when the weather is warm and wet. After few days those damage leaves are falling down and the black spots will appear on young twigs.

To prevent the plant from bigger damage or death it should be treated with specialised fungicide during spring (mid April). You can also prevent water staying on the leaves by simply shaking the plants every morning, before the sun is fully up

Volutella blight

Damaged leaves turn brown and die but stay attached to the plant. The characteristic sign of Volutella is pale pink fungus on the back side of the leaf. This might appear after pruning or during cold winter, when frost damages the leaves. The specialised fungicide should be applied after plant shaping or when you notice the frost damage. If not treated might cause plant death.

Less common fungus diseases

  • Buxus rust
  • Pythium Sp.
  • Phytophora root rot
  • Black root spot

They are not very common problems in domestic gardens as they appear more often in the wild Buxus populations. They are root diseases, which if not treated might cause plant death. They should be treated with specialised fungicide.


Box Tree Caterpillar

These 4 cm long, bright, green caterpillars destroy the plant by eating the leaves very quickly. They need to be treated with a specialised insecticide.

Buxus sucker

The larvae of these small 3-5mm, green insects are covered with white and waxy coat. They prick and suck out the young shoots which cause them to become curly and spoon- shaped. To fight the larvae treat with specialised insecticide applied from April.

Spider Mite

It’s a very small spider – 0.3mm, which causes small, silver coloured stripes on the old leaves. Should be treated in warm weather with a specialised acaricide.

Buxus Gall Mite

Small 0.1mm gall mites suck the sap from the plant shoots. They cause damage on the leaves, which grow small and curled. Should be treated when the damage appears with a specialised acaricide, and only in warm weather.

Mussel Scale

Insects will usually attack old twigs in the plant centre. If not treated it might spread to the whole plant. The twigs and leaves will turn yellow and if this dark brown, small insect isn’t stopped he will finally kill the plant by sucking all the sap out of it. To avoid damage the Buxus should be treated with specialised insecticide in mid May and then repeat after 2 weeks. If you see Mussel signs during the winter, you might be able to fight it with mineral oil.

Buxus leaf-mining gall midger

The larvae which attack the leaves. They cause characteristic yellow and red spots on the leaf surface. Should be treated from the end of April with specialised insecticide.
The healthy Buxus should have a dark, green leaves with bright green new shoots appearing spring time. Unhealthy, weak Buxus are more likely to get the diseases. To prevent problems, you should keep your Buxus well maintained and regularly fed with specialised Buxus feed, sea weed and other products available on the market.

If your Buxus are suffering from any of the above diseases our garden maintenance team will be happy to help. Contact us...