The Fatsia Japonica is a late flowering evergreen shrub that comes to life in the autumn. Its aesthetic beauty fits grandly in a cold hardy tropical garden.
To keep them looking prim and proper, it’s best to learn the pruning techniques for shrubs.
How to Prune Fatsia Japonica
Carry out maintenance pruning annually in spring, and a second (lighter) pruning in mid-summer.
Wounds need time to heal so don’t prune late in summer.
To rejuvenate an overgrown shrub, selective pruning can be done using a combination of heading, thinning, and reduction cuts.
That’s the short of it. The how-to for pruning shrubs is more involved, and that’s what the rest of this page explains. The types of cuts, when to use them, and the how and the why of using them.
Once you experience first-hand how relatively low-maintenance and super hardy these plants are, you may just want more.
You can use the same pruning techniques to shape, and care for similar species in the same genus.
Fatsia is the genus. Japonica is the species.
Other species of Fatsia include the Japonica ‘Spiders Web’, Fatsia ‘Moseri’, Fatsia ‘Annelise’, and the fancy leaved Fatsia ‘Vareigata’.
They all benefit from the same pruning methods as the ‘Japonica’.
Start with what you have and learn the basics to keep it looking lush.
Required Tools and Precautions
If your shrub is young or already maintained, you’ll only need a pair of sharp secateurs (pruning shears).
Which type doesn’t really matter.
If you didn’t know there were different types, here’s what to know.
- Anvil secateurs
These have a single sharp blade, the other is blunt metal.
The cutting action is like putting a stem or branch against a block then pushing down on a knife to cut it.
Anvil cutters have a crushing action.
- Bypass secateurs (the ones I prefer to use)
These have two blades and are like garden scissors for woody plants. The actions are the same.
They get the name because the blades bypass when cutting. They give a cleaner cut.
The ones I use are Felco, I’ve had the same ones for 10 years! I will be doing a review on these soon.
- Loppers
These are like long-reach pruners and they’re unlikely to be required for pruning a japonica shrub, unless you need to cut back an extensively overgrown shrub.
In all cases, sterility is important!
When using your hand tools between jobs, best practice is to always disinfect to prevent the spread of diseases between plants.
When to Prune Fatsia Japonica
Pruning japonicas should always be done in spring.
That’s when the plant is ready to burst into new life!
Growth buds are more visible, and damaged leaves are highly noticeable.
Damaged Fatsia Japonica leaf
At the start of the growth season, you can identify where shoots are going to emerge and decide if you want to keep them or eliminate them.
Nodes and buds are what you need to be looking for.
Buds grow on branches and develop into stems.
Nodes grow on stems and put out leaves.
Cutting above nodes and buds promotes new growth. Cutting beneath either stunts growth!
With that covered, next is…
Planning: The What, and the Why for Pruning Japonicas
Before taking shears to branches and nipping growth back to the bud, take a second and think before acting.
What do you want to achieve?
Have a goal!
Because,
There’s different types of cuts you can do, and specific reasons to use each type. (These are explained further down the page).
As an example,
You could use thinning cuts to remove the lower portion of leaves, opening up the base for summer blooming ground covering plants.
Or,
You can prune a japonica into a tree shape.
At the very minimum, maintenance pruning is what you need to know.
That’s what will let you keep your japonica healthy.
Maintenance Pruning for Fatsia Japonica
For the laid-back gardeners, maintenance pruning is all you need to do – once a year. In the spring.
The only purpose is to remove damaged growth.
Some of the older leaves will die, as can some woody growth if any diseases have taken hold.
Fatal problems are only related to rotted roots. It takes a lot to kill a fatsia shrub.
Dead branches aren’t indicative of a Fatsia Japonica dying.
If a branch looks like it’s decaying, cut into it to see what’s happening.
Woody growth with life left in it has green sap inside the branches. Dead wood doesn’t.
New growth is fast to shoot out so don’t be afraid of cutting this back hard.
You can cut a japonica back by half and it’ll bounce back strong; Provided you do it in the spring and not too late in the summer!
The stems and branches to remove are any that are damaged, straggly, leggy, or the leaves from stems are paler than the rest, or showing irregular spotting.
Ill looking leaves are not worth keeping. They can be indicative of insect damage or disease.
Instead of pinching faded leaves, prune the stem back to the branch and cut it just above the collar. New growth won’t take long to fill out.
That’s the benefit of spring pruning.
Shrubs have an abundance of energy at the start of their active growing season.
Pruning Techniques Explained
When you look at your japonica, you may think it’s too wide, too tall, or too dense.
Specific cuts are used to control the height, width, and density, and you can use a combination of all three cutting techniques for specific shaping.
For all three cuts, it’s important to cut branches at a 45-degree angle so that moisture runs off. You don’t want water resting on open wounds.
1. The heading cut.
Heading cuts are used to shorten branches, not remove them.
The purpose of the heading cut is to encourage denser growth.
On each branch are growth buds. Where you want new growth to start, make a heading cut just above it.
That activates the bud directly beneath the cut, encouraging new shoots.
Don’t use these close the centre of a shrub because then it’ll become too dense.
2. Thinning cuts
Thinning cuts are used to remove entire branches. These go back to the main trunk.
When making these cuts, it’s important to cut near to, but not into, the branch collar.
Where branches join, there’s a stump protruding from it. Like a canker. It’s called a collar.
You want to make a thinning cut close to the collar, without cutting into it. A quarter inch is plenty close.
The collar is thicker so it takes longer to callous over. Until it seals, there’s a higher risk of infection. That’s the reason never to cut into the collar at the base of a branch.
3. Reduction cuts
On shrubs and trees, branches can be leaders and laterals.
Leaders are the thick branches that grow upright. Lateral shoots are those that grow from them.
Reduction cuts change that behaviour.
By cutting a leader about a quarter inch above a lateral branch, the energy that would be channelled into vertical growth, instead goes into lateral growth.
The lateral branch grows longer and stronger, and slower too.
For that reason, these are handy for keeping the height and spread of japonicas in check, while promoting denser bushier growth.
It’s unlikely that you’ll need to use all three cutting techniques, unless you have an unwieldy shrub needing tamed.
Pruning for Recovery: Rejuvenating a Neglected Fatsia Japonica
Garden shrubs are often inherited when you move into a new property. Owing to the hardiness of japonica, it can survive for decades even with extreme neglect.
Surviving isn’t thriving though, so some pruning work will be needed to shape a neglected shrub and give it the best start on its journey to recovery.
If you don’t know much about pruning, this is the most important thing to know…
So long as the plant shows no signs of decay, such as rotting roots, or blackening leaves, there’s nothing serious likely to kill it. When pruning shrubs, where you cut, new growth sprouts. You can give these a hard cut back to near ground level, and they’ll spring back with vigour.
You may as well try to rejuvenate a true gem of an evergreen shrub that’ll add aesthetics to your garden for years to come.
Here’s how…
Remove unhealthy branches first
There’s an old saying that you may be familiar with.
“Out with the old, in with the new”.
That’s what you’re going for here. Inspect the plant for dead and damaged branches first. Those are the first to get rid of.
Follow the branches back to the base and make the cut right above a collar.
The purpose is for new growth to emerge to replace the one you’re removing.
For every damaged branch, repeat the same process until only the healthiest remain.
Selective Thinning
With the oldest of branches gone, next is to do a visual inspection for discoloured leaves.
With neglected japonica shrubs, they’re going to have dense foliage that are heavily overcrowded.
The signs of this are yellowing and brown leaves. These will usually be on thin, straggly, and leggy stems that have been stretching to reach sunlight.
Thin the shrub by removing all the straggly stems. Not just the leaves.
Another reason for thinning is to increase air flow. Too dense, the centre can struggle for oxygen.
As you go, stop, look and assess.
As you’re going through the pruning process, it’s good to take a step back, and visualise what’s going to happen in the coming months.
To visualise where new growth will appear, and what direction it’ll spread.
The goal here is to shape the plant.
Keep in mind the growing habit, which is equal in width and height.
If you cut the plant down by a lot, you’ll want to focus on reduction cuts that reduce height while promoting lateral growth.
That may mean that some of the healthy branches go. So be it!
Without pruning being done, congestion sets in.
On an overgrown shrub, much of the plant lacks air flow and sunlight so doesn’t grow healthy. Pruning is done to open it up to the elements it needs to thrive.
Rejuvenation is about restoring balanced growth.
Not just greener leaves.
As it is an evergreen shrub, it won’t matter if it blooms this autumn or not. The foliage will out, giving you deep green foliage throughout the year.
If you miss the blooms this year after cutting back hard, go through the maintenance pruning process in spring next year.
No doubt, you’ll get the clusters of white flowers forming next autumn.
Keep on with the annual seasonal pruning, and the fatsia japonica shrub can serve your garden well for many more years.
Hopefully you now know how to prune Fatsia Japonica! If you have any other questions, feel free to contact me using the about me page, thanks!
