Buddleia Frequently Asked Questions

What is Buddleia?

Buddleia (Buddleja davidii) is a common flowering plant found throughout Britain and it can often be seen growing along roadside verges, railway lines and areas of urban wasteland. Originally Buddleia was introduced to Britain from China during the late 19th century as a popular ornamental garden plant.  It is also known as Butterfly Bush due to the attraction of butterflies and insects to its brightly coloured flower heads.

What does Buddleia look like?

Buddleia can vary in size depending on location but it is common to find shrubs reaching heights of between 1-5metres. Leaves are elongated and dark green in colour with a finely serrated edge. The underside of the leaves and the stem of Buddleia are covered in very fine white hairs giving it a felt-like appearance and texture. The flower heads of mature Buddleia grow in elongated tapering clusters, usually violet or purple but can also be coloured mauve or white. The flowers are rich in nectar and fragrant, in the height of summer Buddleia is often a haven to the local insect population.

Why is Buddleia a problem?

Due to the high number of seeds produced and its reliance on wind dispersal to spread, it is easy for Buddleia to rapidly colonise large areas in a short space of time. Buddleia can be found growing in a number of difficult to access areas throughout urban and rural environments such as chimney stacks and railway sidings, allowing growth to increase and spread easily if left unchecked. Buddleia, like many invasive species, does not have the biological controls that affect native plants and as a result are able to grow unhindered and easily out-compete the surrounding vegetation for resources.

What damage can Buddleia cause?

As with many weeds, Buddleia seeds are dispersed via wind or waterways and can easily take root in the smallest gaps in rocks or weaknesses in building material such as masonry work or tarmac. Once growth begins Buddleia’s roots can substantially weaken any material it grows from, creating costly repairs and potentially dangerous environments especially in residential areas. Similarly, Buddleia growing on river banks can cause erosion as it spreads and dies off, risking future floods to the area if the problem is not addressed.

How can you kill Buddleia?

Successful control of Buddleia can be difficult due to the number of seeds dispersed annually. Seeds can end up growing in very difficult to access areas and as a result can be a problem to target without the use of specialised equipment. The correct application of herbicides can be very effective in dealing with outbreaks of Buddleia in most environments providing the standards are met to protect the surrounding ecosystem. Smaller Buddleia infestations are shallow rooted and can be hand pulled or mechanically dug out, however care must be taken to remove a majority of the roots.

How can I prevent Buddleia spreading?

The simplest way to prevent it spreading is to not plant it. If Buddleia is already present then it is important to prevent it from seeding by removing its flower heads.

Can I plant Buddleia?

Although there is no law stating you cannot cultivate Buddleia on your property, we would highly advise against doing so.