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Buddleia bushes are beautiful bushes, but they can be a nuisance too, especially when they grow where they are not wanted. The real issue with buddleia is that they self seed freely and will take root anyway from bricks walls to your patio. With their eventual heights of over 10ft and about as wide, established plants can then be very difficult to get rid of.
Removing buddleias can be a handful because they are hardy plants so, simply cutting them down will not do the trick unless you remove or kill the root too.
New shoots will pop up in a matter of time ready to take over where the previous stems left. If you are struggling to remove a buddleia tree from your garden then this is the guide for you.
How to kill a buddleia
One of the best ways to kill a buddleia is to cut it down just above ground level, wait for new growth to shoot and open and then spray with a weedkiller that also kills the roots, usually a weed killer that contains glyphosate. You can also consider using a tree stump killer where you drill holes into the buddleia stump, pour the tree stump killer in the holes and then leave it and wait. Smaller plants can usually just be dug up, just make sure you get all of the roots or it will shoot again.
Buddleia bushes are magnets to pollinators, thus it is easier for them to reproduce and overtake your garden. You may find that the more buddleia you have, the less other plants thrive because of their deep roots. They absorb a lot of the nutrients, leaving plants with shallow roots struggling.
Due to their ability to reproduce fast, these bushes have a negative reputation in the US but also in the UK when they are growing in undesirable locations where they can become a problem. Considered to be a weed, people are advised to regulate the number of buddleia bushes in their garden.
Buddleia bush: How to kill them off
The most effective way to stop buddleia from regrowing is to kill off the roots. Remember that it is possible to divide buddleia roots as a means to propagate the plants. Ideally, cut back the plant close to the ground, drill the centre, pour weed killer/stump killer and cover the plant to prevent it from accessing sunlight. This can be done at any time of year.
Alternatively, you can use a weed killer that contains glyphosate which is usually effective if done right. Glyphosate seeps through the plants through the leaves, especially when applied to fresh growth, this is the key, you need to spray new young growth.
This herbicide is effective against weeds, but it is known as a possible carcinogen for humans, so handle it with care. Roundup is a popular brand associated with successfully killing buddleia, and you can get it online at affordable prices. Gallup Home & Garden Glyphosate Weedkiller is also another good choice.
It is an amazing thing that buddleia grows so easily, however, this is disadvantageous too. Buddleia plants that take root in crevices and cracks can be bad news for buildings. Due to buddleia’s extensive fibrous roots that dig deep into the soil, they can damage walls and even foundations of houses if there are left to get large.
As the plant gets older, the root system enlarges; therefore, needing more space. This will aggravate any cracks and in worst cases, damage the structural integrity of the building.
Buddleia may be invaders, but that does not stop us from having them in the garden. If you undertake preventative measures, it should be easy to keep them under control. One of the things you can do is deadhead the plants you planted in your garden to prevent them from going to seed. Carry out deadheading through the flowering season and continue to experience continuous blooms.
There is also the option of cultivating non-invasive varieties of buddleias such as the Buddleia Asian Moon, and Buddleia Miss Molly among many others. Finally, remove any unwanted buddleias when they are young and can be pulled up easily.
Read next: How to take buddleia cuttings
A good way to prevent these plants from taking over your garden is to cultivate sterile varieties and remove any seedlings that germinate straight away. Killing off an established large buddleia takes some time, but once it is done you will be left just with the trunk, getting rid of this might just take some good old fashioned gardening and a spade.