When To Prune Buddleia And How To Do It The Right Way

If you’re a garden enthusiast who’s proud of their hydrangeas, magnolias and dahlias, then it’s time for your next project. Buddleias! These beautiful plants can grow from about 3 m to 20 m tall, depending on the species as well as the growing conditions. But, if left unpruned, buddleia bush will quickly take over a small garden. What happens then? No need to worry!

Buddleia with two painted butterflies

We learnt the art of pruning buddleia the right way from a colleague, who is an enthusiastic gardener, with plenty of plants and trees growing happily in his backyard. He’s like a garden guru! Want to see what we learnt from him about when to prune buddleia and how to do it the right way? Keep reading!

When is the best time to prune your buddleia?

The million-dollar question is: when is the best time to do it? The best time is in early spring because, in this weather, you can not only take care of it but can also guarantee its growth and sustenance. 

Generally, you should take care of yours in March. However, the exact timing depends on the area you live in. Severe frost – some areas have pretty chilly weather even in late spring – can damage your freshly pruned plants. 

Therefore, you need to know when the last frost in your area will be and then move on with the whole process. It is not the only frost that is harmful to your newly pruned plants. Intense heat can also be detrimental. 

So, you shouldn’t go for it in extreme heat as well. Make sure to check for weather forecasts before you decide on the day of pruning. Just keep in mind that you should not prune the main stems in late summer or late winter. It is better to wait for the next year than risk damaging the pollinators by deadheading them at the wrong time. 

How to prune your buddleia 

As we mentioned above, early spring is the best time when your plant is coming into growth. Here’s what you need to do.

1. Trim Back Growth

To help ensure the best of results, make sure that you trim back the top of the growth and cut it into half to facilitate the plant’s blooming. Cutting this way not only promotes its growth but will also give you better access to the base of the plant. Trim the side shoots as well while you are pruning shrubs in your garden. 

2. Cut Through the Woody Stems

This is a part of the process that a lot of people conveniently miss. You should deadhead the thick and woody stems around 30 cm above ground using either a hard and durable pruning saw or a simple pair of loppers

Gardener hand pruning branches of buddleia

If you want your plant to grow taller than usual, and reach a height of at least 3m, we recommend you leave the stems as long as 60 cm. Even if there is no damage or rot, you should still cut out all the branches to the ground level in the appropriate weather. 

This will not only stimulate evergreen growth but will also result in blooming. Another thing to remember is that stems from the previous year need to be at least 30 cm tall, and you should stop pruning as soon as they reach this height. If you trim more than this, you risk potential damage to the plant. 

3. Remove the Older Branches

To avoid overcrowding of buddleias, make sure that not too many branches sprout. If you sense that your plant is getting too crowded or there isn’t a lot of space between the branches, it is time to cut down some older ones. 

This is the only solution to avoid overcrowding. Most people simply trim their sprouts, but that does nothing to solve the problem. Another difficulty that you may face is to differentiate between the old and new branches. 

However, there is a super-easy way to do this. Young stems tend to be light green, whereas the older stems are darker and have a peeling and woodier appearance. To help ensure the complete removal, you can dig out the older branches by the roots

Extra tips for pruning buddleia

Apart from the information discussed above, there are a couple of other things that you need to remember. Here are some essential tips that will come in handy for you when pruning buddleia.

Buddleia flowers in a garden

1. Remove the Dead Stubs

A major thing that hinders the growth of the buddleia is dead stubs, dead flowers, faded flowers, and broken branches lying around. You need to remove them carefully using loppers or a pruning saw

You can also cut these back to ensure that there is as little dieback as possible. Additionally, you should also decrease the thickness of the crossing branches to ensure that no rubbing occurs. On top of that, removing any twigs or sprouts on the side will also facilitate growth.

However, like most people, don’t think that you are too cruel or too vicious. The buddleia is very strong and capable of growing back fast. 

2. Aim for a Short Strong Framework

You should try to produce a solid but short framework of at least six to seven branches. This may seem scary, but it leads to a lot of good things in the future. 

You may not be able to see a lot of new shoots, but the above step will ensure the timely and efficient growth of your plant. Plus, you can also fork lightly around the base of the plant and relieve some of the built-in compaction that has been caused by continuous movement on the soil. The forking process will also help retain moisture.

Caring for your plant afterwards

Once you’re done with the pruning process, your task ends – or does it? The simple answer to this is no. Even after completing the whole process, there are a couple of things you need to do to ensure that your plant continues getting the care and love that it deserves. 

Child;s hands watering buddleia flowers with a spray bottle

Here’s a list of them:

1. Adding Compost

While hard pruning and even afterwards, make sure that you spread compost and mulch around the buddleia. This will not only help it retain a lot of the moisture but will also help it in fighting off weeds. The ideal standard is to spread compost about 14 cm around the base of the plant.

2. Planting More Buddleias

Once you’re done, you may want to add more plants near the existing ones, but there is an important tip for that. You should always plant newer buddleias around 2 to 3 meters away from all of your existing ones. This will ensure that the plants have more than enough space to grow and prosper. 

3. Watering the Plant

It needs ample amounts of water for proper new growth and to give you the brilliant buddleia flowers. This is why you should make sure that it gets enough water in summer as well as winter. Also, water can sometimes overwhelm new and young buddleias, so you should give them small batches and not overwater them. 

Buddleias don’t tolerate droughts well, so make sure that you also water the soil surrounding your plant. Keep a routine of watering at least once a week before it fully blooms. 

Buddleia flower

Buddleia is a very fast and easy-growing shrub, but many people find it extremely hard to prune it the right way. But, fret not – all you need is the right guidance and a little bit of help. So, if you want to attract colourful, alluring butterflies to your garden, you should plant buddleias, aka butterfly bushes in your garden. It’s easier than you think!

Happy pruning, folks!

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