What are the diseases of boxwood?

Boxwood, also known by its scientific name, Buxus sempervirens (or just Buxus), is a very popular shrub, especially in the area of ​​Europe, Africa and Asia. The most representative characteristic of this is that it is very moldable, and figures can be formed with it. However, it is not exempt from suffering from boxwood diseases.

If you want to know what the usual ones are and how to remedy the problem, here is a guide with the most common boxwood diseases so that you can be attentive to your plant and act before it is too late.

What is boxwood

What is boxwood

Boxwood is a shrub that can reach 12 meters in height (although it is not the most common). It is characterized by having a highly branched stem covered with a bark that, over the years, changes from thin to brittle and between brown and gray in the oldest specimens.

Its leaves can be of different types: elliptical, lanceolate or ovate, but all of them are dark green on the upper side and light green on the underside. These are about 30mm long and end in a small curve at the edge.

It throws flowers, which will appear in spring, very small, and that do not smell, but they are full of nectar. After them, the fruit will appear, which will be brown or gray balls 1cm long, which carry many seeds inside.

The most common boxwood diseases

The most common boxwood diseases

Here are the most common boxwood diseases, those that are more likely to suffer at some point in your long life.

Root rot

One of the first boxwood diseases that we are going to tell you about is this. This is a problem that will cause the boxwood to begin to discolor the leaves and slowly, but without stopping, the plant wilts until it finally dies.

This disease is caused by a fungus, Phytophthora cinnamomi , and when this happens, if it is in a pot you can try to remove it from it, change all the soil and apply a fungal treatment. However, experts know that it is very difficult to save the plant.

In fact, they recommend that, if it happens, it is best to uproot it before it affects other shrubs.


We could say that this is the most serious boxwood disease that exists  and it hurts not only when you suffer from it, but also throughout your life, since it will make you grow less and have less vigor as well. It appears in the spring months, but in winter it may already be infected.

The signs that boxwood suffers from this disease are: leaves turning yellow, some even sticking to the branches, and with pink pustules; branches with pink pustules.

All this is produced by a fungus, Pseudometria rousseliana , and the only solution in these cases is to cut all the branches that are affected, always below where the symptoms begin to be seen, and burn them immediately. The same should be done with fallen leaves, regardless of whether there are signs of boxwood disease or not. It is also recommended, in winter, to apply products rich in copper to prevent the appearance of this fungus.


Rust is a disease that affects many plants, and in the case of boxwood it was not going to be less. It is characterized by being caused by the Puccinia buxu fungus . Among the symptoms that can alert you to the problem is seeing many black dots on the leaves and branches of the bush.

To remedy this, in the case of boxwood you must apply a mixture of sulfur, zineb, maneb and mancozeb, as well as the like, since they are the most effective. Now the plant will need some time to recover.

Leaf mottling

Caused by the fungus Mycosphaerelia patouillardi , the obvious sign that you have it is, without a doubt, that the boxwood begins to make the leaves become more opaque, with white spots on them and, within these, black spots.

It is important that, if that happens, those branches are cut and burned to try not to spread on other box trees.

The Volutella buxi

We mean by this that the boxwood dries up, irretrievably. You will see how your boxwood begins to turn yellow and, in some areas, it will appear as if it has dried out. In some specimens a pink powder may also appear in the area of ​​the leaves, especially in the rainy season.

To fight with this fungus it is best to remove all dry or yellowish areas, as well as the leaves that have fallen to the ground and burn them immediately. In addition, you must apply fungal products and two more actions:

  • Water it without the foliage getting wet
  • Spray every two weeks in spring to give the fungus less opportunity to appear (or reappear).

Macrophoma candellei

This disease causes the boxwood to appear dry, even though it can be very young . You will notice that something is not right if you see little black dots on the back of the leaves, because that is a clear sign of the fungus.

Normally it does not appear in box trees that are well cared for, but in those that are weaker, either because they have deficiencies or excesses in the care or because they have suffered other boxwood diseases or pests.

To eliminate it, the most affected parts will have to be cut, as well as removing the leaves that may be on the ground and burning them. Also, you have to apply an antifungal mixture to help you eradicate it completely.

The other diseases of boxwood: pests

The other diseases of boxwood: pests

In addition to the most common diseases that we have seen of boxwood, you can not forget about pests, which are also diseases, but they are not caused by fungi, but by others. The most commons are:

  • Mealybugs .
  • Spider mite
  • Boxwood mosquito.
  • Nematodes.
  • Meleta.

In general, you have to fight both boxwood diseases and pests as quickly as possible, hence prevention is very important because it will prevent the appearance of problems (and if they do arise, they could be easier to try to have the healthiest plant).

Have you had a problem with a box tree? Any of these diseases or others?

What are the diseases of boxwood?

Leave a Reply

Scroll to top
%d bloggers like this: