Buxus trees are not very prone to many diseases but the most common disease that we hear about troubling Buxus plants is Box Blight. However, Buxus is susceptible to more diseases than just this one.
Fungal diseases and others caused by insects are some less common diseases that Buxus plants are susceptible to.
Buxus sempervirens – Hardy Box for Hedging – 60-80cm tall established Plants
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. Let’s look at the common Buxus problems.
How to spot and treat Buxus Blight
Buxus blight or Box blight is a fungal disease that usually happens when the weather is warm and wet, usually in April or May. It usually appears as black spots on the leaf, and after a few days, the damaged leaves fall off, but the black spots appear on young twigs.
To protect your Buxus plant from further damage, treat your Buxus plant with a fungicide in during months of high humidity in Spring between April and May. Also, avoid misting your plants from the top so that droplets of water will not stay on the leaves and always remember to shake off morning dew from the leaves of your plants.
How do I recognise Buxus blight on my plant?
Buxus blight is easily recognized as dark brown or black patches on the leaves of a Buxus plant, eventually turning the entire infected leaves brown and causing the infected leaves to drop.
How can I prevent Buxus blight?
Buxus blight occurs more frequently in April and May when the weather is humid, warm, and wet. Basically, it is caused when water settles on the leaves of your plant frequently so the easiest way to prevent the disease is by avoiding this. Simply shake morning dew off your Buxus plants every morning before sunrise before the water dries on the leaves of the plant.
To revive your Buxus plant after this infection…
To revive your plants after infection, spray the leaves with a specialised fungicide and for effectiveness, repeat the process after 14 days.
BUXUS GUIDES & Further Reading
- Buxus Grow Guide – Learn how to get the best from your Buxus
- How to make your buxus grow faster
- How to save a dying Buxus & common problems
- When is best to prune or trim your buxus
- How far apart should buxus be planted
Buxus can be grown into many shapes such as balls, pyramids, spirals, lollipop, or just hedges and topiary. Other plants could be used such as spiral bay trees, ilex crenata, taxus baccata or yew for yew balls or twisted yew trees
How to spot and treat Box Tree Caterpillar
These caterpillars are about 4 cm long and can easily destroy you Buxus plants by eating the leaves of the plant. They destroy the foliage by eating it, leaving ugly holes and makes your plant lose its beauty. They can be treated with a special insecticide.
How to spot and treat Buxus sucker
These are the larvae of small green insects and are about 3-5 millimetres long. They are easy to identify because they are often covered in a white waxy coat. They damage the young shoot of Buxus plants by pricking and sucking at the roots and this causes them to become spoon-shaped and curly because of the loss of essential nutrients. It can be handled easily by spraying your Buxus plant with a specialized insecticide in spring.
How to spot and treat Spider Mite
This is a tiny spider that strings webs on old leaves and causes small and silver stripes to form on the leaves. It should be treated during warmer seasons with an acaricide.
How to spot and treat Buxus Gall Mite
These are also one of the small insects that cause damage to Buxus plants. They are small gall mites about 0.1 mm. They damage the leaves of your Buxus plant by sucking out the sap from the plant’s shoots causing the leaves to remain small and curl at the edges. They can be treated by using an acaricide during warm seasons like spring and summer.
How to spot and treat Mussel Scale
These insects will attack old twigs at the centre of the plant and if not treated will affect and damage the entire plant. The presence of mussel scales can be easily identified when the leaves and twigs of the Buxus plant turn yellow before finally turning dark brown. At the point where the twigs and leaves turn dark brown, the infestation is deep and will likely kill the plant.
The destruction of your plant by mussel scales can be stopped by applying an insecticide after identification. Apply the insecticide in May and repeat the process after 2 weeks. Mussel scales that attack your plants in winter can be eradicated with mineral oil.
How to spot and treat Buxus leaf-mining gall midges
These larvae attack new and weak Buxus twigs and stem before they are well established. They can be identified by red and yellow spots that appear on the surface of the leaves.
To prevent the presence of this destructive insect, keep your Buxus plant well maintained and feed it regularly with a recommended Buxus feed. However, where the insects are already present on your Buxus plant you can treat it in Spring, at the end of April with a specialised insecticide.
To prevent your Buxus plant from further damage, treat it with a fungicide in mid-April. Additionally, you can prevent the build-up of Buxus leaf-mining gallmidger and other insects that attack Buxus by preventing water from staying on the leaves.
How to spot and treat Volutella blight
It is a fungus disease that is characterised by a pale pink fungus that grows on the underside of Buxus leaves. It usually occurs during winter when frost damages the leaves or after hard pruning. It causes the leaves to turn brown and die without falling off the tree.
If you notice this disease, use a specialised fungicide after plant shaping and training or during winter if the foliage starts to experience damage. In the case where it is not treated, it can cause the entire plant to die.
How To Revive A Buxus Plant
Buxus plants are generally easy to grow in reasonable garden conditions but several things may affect the growth of your Buxus plant and cause it to look unhealthy and this can lead to the eventual death of your plant. The most common problem that may cause your Buxus plant to wither away is a fungal disease called Buxus blight (Box blight).
FAQ
Why is my boxwood drooping?
In most cases, this occurs after the plant has suffered some stress, such as winter injury, poor pruning or excessive water in the soil.
Why do boxwood leaves turn yellow?
The most common reasons for yellowing and browning of boxwoods are rotting in the roots, nematode infestation, winter damage, ageing, insect infestation, and lack of adequate irrigation.
Can you overwater boxwood?
Yes, it usually shows in the yellowing and wilting of the leaves.
