Should I replace my Photonia hedge?

[Ngnra]

I have photonia hedge at the edge of the patio. There are about 4 plants which were all planted 15 years ago with the new house.

they are all tall with much less screening in the lower level. I didn’t prune them regularly, but a a couple of times in the last few years.

I wonder if they all have to be replaced with new photonics or something else.

Please advise.

Photonia hedge

[EricL]

Hello@Ngnra

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thank you for sharing your question about your photinia hedge.

The average lifespan of a photinia hedge is 50 years. It grows to maturity in 12 years. I think the hedge can still be trained to grow into the shape you're hoping for. A bit of pruning and some well-timed application of fertilizer should enliven your photinia back to life. 

Ideally, the best time to prune the photinia is after spring blooming and then again after fall growth. Your objective is to trim the bottom part of your hedge to encourage growth in this area. Planting a new hedge means that you'll need to wait again for the plant to reach maturity so that it forms a sizeable hedge.

Here is a handy link: How to grow, prune and propagate photinia

Let me call on our experienced members @Adam_W and @Noelle for their recommendations.

If you need further assistance, please let us know.

Eric

[Ngnra]

Many thanks for your reply. I am learning 

[Noelle · Accepted solution]

Hi @Ngnra 

In addition to the excellent advice from Eric, I would also suggest cutting the tops of each one, to encourage lots of new growth down lower. Pruning the top will result in overall bushiness or thickening of the leafy growth all over.

[Ngnra]

My photonia hedges appear diseased. Something wrong with the trunk of the tree.

photo attached for your review and comment.

please advise.Photonia trunkAdjacent photonia trunk

[MitchellMc]

Hi @Ngnra,

Was there an aspect of the trunks that you believed looked particularly diseased? If it's the green growth, that's a natural phenomenon and is just lichen and nothing to be concerned about. However, you are getting a bit of rot and cracking of the branches you're pruning, so it might be an idea to paint the ends after cutting with Steri-Prune.

How's the leaf growth on the plant? Does it otherwise appear healthy, or are you concerned about the whole plant's appearance?

I look forward to hearing further details and assisting with your questions.

Mitchell

[Ngnra]

Please find attached another photo of the trees as a whole. My concern was about the trunk. The plants are more than 15 years old. I have trimmed them substantially this winter as was advised by you last year. You can see red shoots on them.

Pleas advise.

[MitchellMc]

I can see that you've got some reasonable shoots going on from the trim @Ngnra. Your plants are hard up against a fence, and the top foliage overshadows the lower trunk. Shoots will typically not form in shadowed areas, and getting the plant to back bud onto the old growth would be difficult. As long as the plant can keep growing outwards, finding more light, it won't put energy into growing branches and leaves in areas that receive less light, like the understorey or close to the trunk. This process is similar to the side that's hard up against the fence. No growth is seen there, as it's shadowed by the fence.

I imagine it's a principle similar to the one I used in Bonsai. You would trim the branch back to the first leaf on the lanky branch. That stops the branch from growing outwards and forces it to produce new shoots on old wood back towards the trunk. Sometimes this works, sometimes it doesn't.

It's likely taken several years to lose all the internal leaves and those lower down. I suspect it will take several years to revert the process by continuously doing hard prunes until you've developed enough shoots to fill in the empty space. However, if you only hard prune the top and not the front, that's where you'll see the new growth come back. It might require you to do an even harder prune on the top and take it down 30cm below the fence line to see the buds form lower down. It is a battle between not removing too much from the height and, at the same time, forcing lower buds. 

Let me tag @Noelle to get her thoughts.

Mitchell

[Noelle]

All that nice new growth is at the top of slender stems that have been trimmed back. Nice to see but not where you want it. 

You can see where the shrubs have been cut back very hard previously about 30-40cm above soil level and you can clearly see that most of those slender stems arise from around that severe pruning level. Those shoots should have been cut back to within about 30cm of the original cut, to encourage denser regrowth low down on them.

You have a couple of options, depending on what you want to achieve long term:

- cutting back hard as recommended by Mitchell (or even harder!) every year for the next however many years it will take to produce a dense hedge from about 30cm above the ground;

- trim as you did last year and be resigned to the fact that the intermediate zone between the soil and the top of the fence is not going to have much leaf cover.

[Ngnra]

Many thanks for your comments.

what do you think about planting a new seedling next to these trees?