Pieris advice, please

KC_2

Hello there, I was wondering if anyone could tell me whether I can risk reshaping/ cutting back a pieris that is in a pot by the front door. I looked for info on the web and read that I should wait until spring as potential new shoots would be killed off by the impending winter. However, it is looking very sad. My instinct tells me that it is pot bound but I don't have space to repot it into a larger pot for by the front door. Any advice would be gratefully received. 

The last time I visited here I got some absolutely brilliant acer advice from several very friendly regulars, so I'm hoping you'll be able to give me some advice this time too!

Many thanks.

Plantminded

Pieris usually flower between March and May, so cutting any stems now will remove next year's flowers.  However, it sounds like you plant is not performing well due to being pot bound.  If there's no space at your front door for a larger pot, is there a space elsewhere?  Ideally the shrub would be better off in the ground.  If you want to keep it where it is in its existing pot then removing it from its pot, gently teasing away the existing compost and then replanting the plant in fresh compost may help, but it's not ideal.  It would then be better to cut the plant back and accept that you'll have no flowers next year.  Use a soil based compost, not MPC, and keep it moist.

KC_2

Thank you Plantminded, that's very helpful. I am less worried about removing next year's flowers, I daresay the leaves will still do their red thing when they're new before turnning green! We have limited ground space available, unfortunately, so I would like to keep it where it is if I can.

The good thing is that I won't kill it off altogether if I shape it now. And that's what was worrying me.

Is MPC Multi Purpose Compost? I do have some "topsoil" as well as MPC so I will also add some fresh soil to the pot. 

punkdoc

if it is pot bound, pruning will not help it, you either need a bigger pot, or, you could root prune it.

Pete.8

I agree that root pruning is the way to go.
You can safely remove up to 1/3 of the roots.
The big roots are mainly there for stability, so those are the roots to prune.
The feeder roots are the really fine hair-like roots - try not to lose too many of them.
I'd also recommend an ericaceous compost as pieris much prefer an acidic soil.

Soil-based ericaceous compost isn't widely available although John Innes ericaceous compost does exist if you can find it.

If it were me, I'd bay a bag of ericaceous compost and mix it with about 50% topsoil.
I'd also add a good 10-15% grit to ensure good drainage.
Also ensure the pot is raised off the ground a little to ensure good drainage especially over the winter.

KC_2

Thanks, all. I just realised, I have ericacious compost as I bought it when I got the pieris and the acer at a good garden centre (recommended here in my previous encounter with you nice people!) so that's fine.

I'm afraid I don't think I'm really up to root pruning ... it's beyond my skillset ... so I will do what I can! Thank you for reminding me about the ericacious compost, Pete.8 

Pete.8

KC_2 said:

I'm afraid I don't think I'm really up to root pruning ... it's beyond my skillset ... so I will do what I can! Thank you for reminding me about the ericacious compost, Pete.8 

Root pruning is nothing to be afraid of.
If you feel unsure about it the easiest way is to remove it from its pot, lay it on its side then just saw a few inches off the bottom (about 1/4 to 1/3) - I use an old bread knife or an old saw. If there's lots of dangly roots, just cut them off.
You can then put a layer of grit in the bottom of the pot and some fresh compost, then pop your pieris back on the top and give it a thorough watering.
The damage you cause to the roots is good and will encourage lots of fresh new feeder roots.
It is important to keep the pot raised off the ground. You can buy pot feet cheaply.
I just 3-4 small offcuts of wood, or even a few bits of polystyrene.

Fairygirl

Bear in mind that compost alone isn't enough for shrubs in pots long term, so some extra soil is needed. Like rhodos etc, they don't need acidic soil, just soil that isn't alkaline, but in a pot it's easier to have a mix   
A bigger pot might be easier if you don't feel able to root prune, but many of them want to be quite sizeable shrubs, so it'll depend which one you have. If you don't have room for a bigger pot, you may have to consider a different plant altogether. 
It may have suffered badly if it's been dried out in summer, and  it can be hard to rehydrate them. They're best in shadier sites, but will manage sun if they're in the ground. All potted plants need more attention. 
If you have a photo, that will always help with extra advice though. 

KC_2

Pete 8, thanks for the advice, but I still feel daunted 

Thanks, Fairygirl. I will see if I can get a decent photo - good idea!

Plantminded

Root pruning is definitely an option if you don't have space for a bigger pot or space in the ground.  As @Pete.8 says, it's really easy.  Just lift your plant from its pot, lay it down sideways and cut the bottom third off, straight across as if you are cutting off a large slice of bread.  Fill the bottom third of your pot with fresh compost and put your pruned rootball on top.  I did this last year with two Buxus, using a pruning saw.  I was anxious that I'd been a bit brutal but they have since thrived and done very well.  There's lots of videos online about root pruning if that helps you to watch it being done.

KC_2

Thank you!