My inbox has been filled lately with pruning questions.  Specifically, how to prune back overgrown flowering shrubs.

Chihuahuan Sage (Leucophyllum laevigatum)

Chihuahuan Sage (Leucophyllum laevigatum)

You may be wondering why you need to severely prune back overgrown shrubs?

Well, as you can see from the photo, above – as a shrub’s branches age, they produce fewer leaves and flowers.  As time passes – these branches die, which leave ugly, bare areas.

Here are a few more examples of overgrown shrubs that need to be severely pruned back…

'White Cloud' Texas Sage (Leucophyllum frutescens 'White Cloud')

‘White Cloud’ Texas Sage (Leucophyllum frutescens ‘White Cloud’)

You may think the formally pruned sage shrubs in the photo above, look okay besides being a bit on the large side.

But, what you don’t see is a large amount of dead branches inside.  In reality, these shrubs are covered in a very thin layer of growth.

overgrown shrubs

Here is an example of old Cassia (Senna nemophila) shrubs that have only been pruned formally.  You can see that there are more dead areas than live growth.

So, how do you go about severely pruning old, overgrown shrubs back?

First of all – don’t do this during cooler months because it will take your shrubs a very long time to grow back. In addition, it can make frost-tender shrubs more susceptible to frost damage.  Wait until spring for pruning back summer-flowering shrubs such as bougainvillea, sage, oleanders, etc.

You need a good pair of loppers and sometimes a pruning saw and you are ready to go. Simply prune your shrub back until there is only about 1 – 2 ft left.

Hedge trimmers can help if you use them to remove the outer part of the shrub and then you can get your loppers inside to prune off larger branches toward the base.

Below, are photos of ‘Rio Bravo’ Sage (Leucophyllum langmaniae ‘Rio Bravo’) shrubs that started out overgrown, were pruned back severely, and grew back.

overgrown shrubs

Overgrown shrubs.

overgrown shrubs

Pruned back to 1 ft.

This is the ugly stage.  But you need to go through this ‘awkward’ stage to achieve beautiful, healthy shrubs.

I promise that it doesn’t last long…

overgrown shrubs

New growth appears 3 weeks later

8 weeks after pruning

8 weeks after pruning.

12 weeks after severe pruning.

12 weeks after severe pruning.

You can see that the severe pruning caused the shrub to grow young, new branches that produce beautiful green growth and flowers.

overgrown shrubs

**Although severe renewal pruning keeps your shrubs healthy and attractive – there are a few cases when an old, overgrown shrub won’t grow back. It is doubtful that the Cassia shrubs, above, will survive for long either with or without severe pruning).

This usually indicates that the shrub has declined too much and would not have survived for long even without pruning.  If this happens, you are better off replacing your shrub.**  

Hand pruners, pruning saw and loppers

Hand pruners, pruning saw and loppers

A good guideline for severely pruning your shrubs is to do this every 3 years or so. Of course, you can do this every year if you like to help keep your shrubs from outgrowing their space.

I hope that this helps to answer some of your questions.

If you would like to learn more about how to prune shrubs the right way, I invite you to learn more about my popular online shrub pruning workshop.   

Many people tell me that they are tired of their boring, round green shrubs.  Often, they are surprised when I tell them that those ‘boring’ green balls would actually flower if given a chance.

So, how do you take those boring green balls and turn them into beautiful, flowering shrubs?  

pruning flowering shrubs

‘Green Cloud’ Texas Sage shrubs

The first step is to rejuvenate your green ‘balls’ by severely pruning them back.

Now I warn you, this is an ugly stage.  Your shrubs will look like a bunch of sticks poking out of the ground.

pruning flowering shrubs

Red Bird-of-Paradise shrubs, newly pruned.

This is best done at certain times of the year, depending on what type of flowering shrub you have.  For example, if you severely prune summer-flowering shrubs back in December, you will have to wait a long time for them to leaf out, once the weather warms.

I pruned the ‘Rio Bravo’ Sage (Leucophyllum langmaniae ‘Rio Bravo’) shrub below in March and by early April, it had already begun to produce new branches.  

pruning flowering shrubs

‘Rio Bravo’ Sage, 1 month after severely pruning.

So, when should you prune your shrubs?

Here is a list of some of the most common shrubs in the low desert and when they should be pruned. (If you live in the high desert, you can adjust the timing by a month or so later.)

Bougainvillea

Bougainvillea

Bougainvillea (Bougainvillea species) – March

Red Bird-of-Paradise (Caesalpinia pulcherrima) – March

Baja Fairy Duster (Calliandra californica) – March

Cassia species (Senna species) – May (once flowering is finished)

Brittlebush (Encelia farinosa) – June

Valentine Bush (Eremophila maculata ‘Valentine’) – May

Texas Sage (Leucophyllum species) – March

Oleander (Nerium oleander) – May or June

Yellow Bells (Tecoma stans) – March

Cape Honeysuckle (Tecomaria capensis) – March or April

If you look closely at the list above, you can see that in most cases these shrubs are either pruned once they have finished flowering OR just after the danger of frost is over in the spring.

The reward for your efforts is a beautiful, flowering shrub like the ‘Green Cloud’ Texas Sage, below.

'Green Cloud' Texas Sage

‘Green Cloud’ Texas Sage

If your shrub is getting a bit large later in the year, you can prune it using hand pruners and removing no more then 1/3 of the growth.  Just be careful not to use hedge-trimmers.

So, do you have to prune your flowering shrubs severely every year?

Absolutely not.

As long as your shrub is attractive and not outgrowing its space, you can save severe pruning for every 3 years or so, which will remove older branches and cause new ones to grow in their place.  This is what I do in my own garden.

Want to learn about pruning flowering shrubs the right way? I invite you to check out my popular online pruning workshop. I’ll teach you how to maintain beautiful flowering shrubs by pruning twice a year or less.