Container planting advice, please!

You can see immediately from the shape it will be a nightmare getting a pot bound plant out of the pot.
Definitely do not put a Fatsia into this pot. Garden centres sell them as house plants they are trees. I have two Fatsia growing in large pots and they are very difficult because of the weight when you need to re pot.
As someone suggested use the pot as a container for a plastic pot, this of course will reduce the size of the route ball you can have.
If you are wanting a shrub look for something which is dwarf.
I have a pr of dwarf Azaleas which look great in flower but need re potting into 20 cm pots back end this year.
I've just re potted a large Rhododendron and it took me and hubby to do the job.

The pot pictures doesn't have drainage holes, and I'm not going to risk drilling some!

do stand it on pot feet so it can drain

I had an ali baba pot and had to break the pot to get the plant out, the roots were so very tough. I would suggest a plant that is a bit like bonsai, in that it is happy in that size of pot for many years. I had one in a pot for over 15 years and eventually had to give it to dd, it is still thriving in the same pot. A red acer palmatum, it will eventually make a most beautiful plant. All I ever did every few years was scrape some soil out and replace it with some new

Thank you shysal I had a lovely agapanthus in a pot, the winter that saw off the palm did for that too. And Trevor the tree fern.

Sorry to admit that winter coincided with a sad event, and it was in May when I should have been looking after things that I had a bit of a crash and burn meltdown.

Starting to try to get that area going again, it's the deck that our French windows open onto, South facing, real suntrap.

I have a couple of pots of annuals planted up, which are looking cheerful, and 2 large pots with my sunflowers (which I grew from seed) which are looking quite promising!

Well done Mr P for not breaking the pot! I have given up buying that shape because I usually end up breaking them.

Some good ideas given already.
I have a variegated Fatsia Japonica, which is striking and the glossy green ones are nice too, look exotic but hardy.

Being in the West Country an Agapanthus would do well.

I am fond of the little bright green conifers with trailing ivy plus something seasonal which can be changed, and underplanted with bulbs.

Have fun making your choice.

Thank you all!

Had a Fatsia Japonica (called Freda, Mr P can't remember plant names, so it was Freda Fatsia, Walter Windmill Palm, Colin Cordyline etc )

What a great suggestion for putting a plastic pot inside the terracotta one! Why on earth didn't I think of that? Because I'm a numpty, that's why

I've got Hostas and California poppy in one and geraniums in the others.

I have similar pots planted with summer and winter heather. There are flowers for most of the year.

As the 2 previous posters have said, phoenix, anything you like but if this is to be a fairly permanent display, maybe a plant in a similar sized plastic pot. Come harsh weather, accident or a change of mind you can then take it out and swap for something else. I have a pot similar to yours containing an umbrella plant. I’ve another with just grass - I’m guessing Stipa? It’s green and blonde and waves in the wind like Tina Turner’s famous hairstyle! If you want some seasonal colour now, put in some crocks for drainage and plant “A thriller, a filler and a spiller” as US garden videos are wont to say. Meaning something tall and striking, some pretty shorter plants and then a couple which will spill over the edges. Feed regularly and it’ll be a real showstopper in the colours you choose. When the season’s over, emptying the pot will be a breeze and no bad language necessary.

Phoenix has your terracotta pot got drainage holes in the bottom? If not, you'd be best doing as another poster has said and planting something into a plastic pot and then putting that into the terracotta pot. If you pot does have drainage holes, put a scattering of broken plant pot bits or small pebbles in the bottom before you put soil in. This helps with drainage and it also forms a layer to stop the plants roots from growing down into the holes and making it almost impossible to get back out in the future.

As for what to plant in it; anything you like really! If you fancy something colourful, how about bedding plants for the summer season? Or an azalea that's specifically for pot growing? Or for something dramatic and architectural a cordeline? They come in colours green, red, orange, line green or almost black. Pic attached.

Agapanthus? Always remind me of summer and weddings!

Phoenix anything you like, really, that's not too fast growing. I have all sorts of shrubs in pots outdoors - roses, a hydrangea, a dogwood with brilliant orange stems in the winter, a snowberry, a sambucus, the list goes on.
My favourite is a standard azalea that I got from Morrison's for £5. When it finished flowering indoors, I potted it up in ericaceous compost and it's doing really well outdoors, with lots of new growth.

Lovely pot, how about a Fatsia Japonica, the large green leaves would complement the pot.
I have some similar pots and know the difficulty removing pot bound plants. Now I put the plant into a plastic pot that fits inside the decorative one. Not only does it make repotting easier, it’s another layer of protecting the roots against frost.