Japanese Pieris for pots on (mostly) shaded patio

Hi,

I recently moved 2 large-ish pots to my patio. As my garden is Northwest facing, for most of the day the area is shaded.

Inspired by a recent thread about plants with Winter interest, I thought it would be a good opportunity to introduce 2 evergreen plants and after considering various options, i decided on Japanese Pieris / Andromeda.

I already knew some basic things about them: that they are evergreen, prefer partial shade & acidic soil, have a relatively tidy habit, are slow growing and I had seen them with bright red new growth. However I did some additional research, and was quite surprised at the range of options. So I thought I would share here, just in case someone is at the same point that I was.

• Their final size can vary greatly based on the variety, from 50-60cm to over 4m.
• Some have variegated foliage.
• The most common cultivars are Mountain Fire and Flaming Silver. Both of them have very intense red new growth, that's why I had that image in my mind.
• I am actually not a fan of that fiery red growth myself, as it doesn't really go with the rest of my garden. However, there are other options. Cavatine for instance, which is also known for being a very prolific bloomer, has green new growth. Prelude is said to have pink new growth, though I haven't found any photos of it so I don't know if they just mean a pink-ish red. Katsura, another well reviewed pieris, has deep wine-red growth. Ralto is said to have bronze-orange new growth.
• Most pieris plants have white bell shaped blooms, though there are some with light pink and dark pink ones. My personal preference is for the darker pink ones, which are normally found on relatively large pieris such as Passion, but there are some more compact ones such as Polar Passion and the aforementioned Ralto.
• They hate being overwatered, so good drainage is very important.

In the end, ordered 2 Pieris Ralto. There isn't a lot of information about this cultivar online but it seems to have all the elements I want: (a) relatively compact, (b) new growth that is not fiery red, (c) pink flowers and (d) variegated foliage. Had it not been for point (b), I probably would have gone for Polar Passion, as there is more information online about that.

Only time will tell if I have chosen wisely

 

Very interesting to have Pieris in pots, @CostasK . I though those plants grow better in soil.
How much sunshine do you get in summer?
My garden is N and it's a problem to find plants that live in 24/7 shade from End of September up to April.

 

Hi @simone_in_wiltshire

A lot of it is trial and error to be honest, but I have read that they do well in pots (if we are talking about the more compact cultivars).

In the past I actually had a pieris and I remember that when I transferred it to a pot to gift it, the root system was quite small. I also remember that while the tag said full sun / part shade, the new growth was getting scorched by the sun and I had to move it.

I am not sure exactly how much sun the area gets in summer to be honest - probably around 3. My understanding is that if it doesn't get enough sun, that affects flowering etc, it's not that the plant dies. But we shall see

 

They're fine in pots for a while, but ultimately, like most shrubs, they're better in the ground.
Where I am, they're fine in quite sunny positions, but we don't have the extreme heat that southern areas have. An aspect of west round to east is better. They also flower perfectly well in those aspects.
When it comes to watering, they're actually quite hard to overwater. They wouldn't grow like weeds here if they didn't like water! The problem in a pot is drainage, so that's the main factor, but that's the same for everything potted.
Like many shrubs of this type - they don't actually need acidic soil in order to thrive, but they don't like being in alkaline conditions, so neutral to acidic is fine.
There are certainly many options, but some get bigger than others, and they're certainly slow growing even in perfect conditions, but in the ground, once established, many grow quite quickly.

Anything in a pot, especially a woody shrub, will always need more attention than in the ground, and the growing medium has to be decent and soil based, not just compost.

 

Good point about drainage versus overwatering @fairygirl. I meant that it isn't very forgiving of wet feet, but it is a good distinction as that is not the same.

Thanks for the information about the medium. I will try to source loam-based erricaceous peat free compost or - failing that- mix peat free erricaceous compost with some topsoil, well rotted manure and potting grit.

It's interesting how microclimates can affect a plant. I actually live in a seaside town in the North of England, so it's not quite as warm as down South, but not the coldest either. The pieris I had in the past really hated full sun, it got quite badly scorched. At some point I moved it behind a large rose so that it was rarely getting direct sun (but it still wasn't a dark area) and it was much happier.

My soil borders on the alkaline, so I kept trying to amend it. It felt like a losing battle. Eventually I put it in a pot with erricaceous compost and gifted it to my partner's mother. It's doing a lot better these days.

I suspect that some of the dwarf varieties might be ok long term in a large pot (e.g. cavatine, which only grows to about 60x60 cm).

I do realise that I am pushing it a bit with the ones I have chosen myself, both in relation to shade as well as pot size. Regarding the latter, the pots have a diameter of 40-odd cm and a height of around 50cm, so should be OK for a while. Eventually, if the plants are reasonably happy with the amount of light, I would be happy to get bigger pots

 

Very few plants are happy with permanent wet feet. Just pond plants really!
It's always a losing battle trying to permanently amend soil ph, so if you desperately want a plant that needs different conditions, pots or purpose built beds are the solution. That could be better long term for you if pots aren't suiting well enough- build something that gives adequate room for roots to spread and get down well to allow the plant to thrive. The pots you have sound decent though, so should be fine for a good length of time.
Large pots can be hideously expensive too, and there's always that danger of wet/freeze affecting them and then doing the same to the plants' roots themselves.
The growing medium is important, and certainly ensuring good drainage, so check that holes don't get blocked, but also remember that in summer conditions, or in longer dry spells, that evergreen foliage can prevent moisture getting in, so you have to check regularly to ensure they don't dry out. A mulch to keep the surface tidy, and to help retain moisture is always a good idea with anything potted. Bark is good for that sort of shrub, but gravel is also nice.
Look forward to seeing what you do

 

Thanks again for the helpful tips @fairygirl I followed your guidance regarding the compost and planted today.

Before that, I had to move the plants that used to be in those 2 pots to the ground, after some re-jigging which included quite a bit of digging. The garden looks worse than before because of that process and of course the new plants will need time to grow, right now they are a bit too small for their intented purpose, but I know I will need to be patient

 

That looks fine @CostasK . It'll be a while before the foliage spreads enough and fills the pot surface, so you shouldn't have too much of a problem with them getting dried out. Probably a wee bit over potted, but they're tough plants so it's not as much of a problem as it would be with something a bit more delicate, and woody shrubs are bothered far less anyway. They'll make a nice feature.
I'm not familiar with that variety, but I had a look and it still seems to get to a decent size, but it will take a while. Just keep an eye on it for wind damage through winter as it seems to be more vulnerable to that, and variegated foliage always tends to be more susceptible to that - on many plants.
They do tend to produce new varieties of all sorts of plants nowadays, often with very few differences from others, but that's how it is now - it's a big business.

The only other thing I'd say is - make sure you have some pot feet to ensure excess water gets away well as they're on a hard surface.

 

Thanks @fairygirl

Yes, I have read that they hate cold wind. I am debating whether to use fleece (and also cover the pot with bubble wrap) or to just move them inside the conservatory when the weather gets really cold (it's unheated and gets plenty of air because we are always letting the dog out, so it shouldn't get too dry). I would obviously be adding saucers in that case.

I did use something similar to pot feet! They are called "pot mate" Amazon.co.uk They seem to be working well

 

I wouldn't over cosset them. Just move them against a house wall if you have rough weather. You end up with weak plants otherwise. They'll adjust to your conditions over the next few years.

That's good that you have some feet. I couldn't see anything in your pix which was why I mentioned it. I don't have pots on hard landscaping as my back garden's gravelled, but I just use bits of timber battens for mine if needed.