Very large hardy star jasmine never flowers!

[Vodkacranberryplease]

I have a very large hardy jasmine on a south east facing wall that gets good morning sun. It's in a large planter 60cm sq. Grows well fed and watered very fairly regularly. It does not flower and never really has (apart from a few). It's also looking a bit tatty.
Meanwhile Homebase non hardy ones that aren't even supposed to be hardy have lived and were flowering well in pots very neglected - one north east facing under a tree (moved to north east not under a tree and not flowering but that could just be the end. And a south west but very shady spot (2 hours of sun) was going crazy earlier this year.

I think I need to move it but getting it out of the pot is a mission and even moving it is too.

So, jasmines. They seem to like the shade more than the websites say and I don't know what to do.

Can anyone help? My neighbours ones (front of houses) are in flower. This is a prime spot and I'd hoped for beautiful scented flowers in summer!

If I have to get it out of the pot I'll have to cut its roots. Will that stop it flowering this year?

Adding a pic so you can see.

The right way up. Think the pot is 45cm sq too

Mines abound the same size and only has two flowering stems. It’s west facing so gets some shade and sun, but like you I don’t know why it doesn’t flower. It’s watered and fed.

I've looked it up but everywhere says it needs sun! Which it gets. Possibly a 'high potash fertiliser' whatever the fuck that is? I've got miracle grow and leaf mould and that's it. It's tomato food I think.

I don’t know if it’s a high potash fertiliser as I’m not great at this gardening malarkey, but I read about digging in some fish blood and bone around my honeysuckle. I assume that would be similar. Might be worth a google.

Thanks - me too! I've got some stuff - Jacks Magic that I suspect might be that kind of thing.

How long has it been in its pot? I wonder whether the compost in the pot is old and exhausted and the feeding isn't making up for that. If repotting isn't feasible, you could dig out as much compost as you can and replace it with fresh. Or are you pruning at the wrong time?

Top tips from the RHS

I'm not sure that is jasmine, @Vodkacranberryplease. It looks like Trachelospermum jasminoides (star jasmine) which isn't actually a jasmine.

If it is jasmine, are you pruning it? True jasmines only flower from the previous year's new growth so if you prune it, it won't flower.

If it is Trachelospermum jasminoides, they like regular water but free draining, loamy/sandy soil so the roots aren't wet. They don't like drying winds either. The leaves look a bit pale and dry in the photo (it could be the photo though), they should be dark green and glossy. There are a lot of red leaves too. They do turn red in winter but they shouldn't be doing that now, something is stressing it.

I would say it needs a well balanced fertiliser at the moment to get it back in good health. The problem with that though is that it will put all it's energy in new growth if you provide it with ample nitrogen and water and won't flower. Once it is healthy, you could switch to a high potash fertiliser like Tomorite to try and push it into flowering.

If you need to cut the roots to repot it, it definitely needs repotting this year.

Interesting advice goingoverground mine is indeed a Trachelospermum jasminoides, with the same problem. I have followed the RHS advice When it was planted in the large pot and it is planted in a sheltered courtyard. I have only two or three flower bracts and do feed it.
As The RHS advises any necessary pruning in early spring I shall wait till next year to repot, although I’m loathed to lose the growth it has.

I agree it's a trachelospermum jasminoides or star jasmine (which is what OP titled the thread) - mine is stressed at the moment because the foxes dug it up and also has some red leaves. Apologies if I muddied the waters with the RHS link. I did it in a hurry and thought (perhaps wrongly) that they lumped in trachelospermum in their coverage of 'jasmines'.

RHS advice on trachelospermum

Yes it's definitely a trachelospermum jasminoides. So I was going to put an annual (thunbergia) in the pot (at least it will flower!) and as I went to dig into the soil I realised it was taken up with roots. So it's just one big rootball!

So it looks like I need to wrestle it out of the pot but I haven't got a border to put it in apart ftom a spot with much less sun.

Is it possible to cut some of the roots away, replace the soil (john innes no 3??) and put it back, then feed it as described? I don't need it to grow I want it to flower!

I've just given it a massive feed and water (miracle grow) but there's not much soil in the pot I think, but I'm a big of a newbie and not sure if cutting roots is a thing. I know some plants hate having their roots disturbed

I think I have a couple of things like that, probably outgrown their pots root wise but there's nowhere much to put them. If I could get them out, trim the roots and freshen the soil without ruining them it would be great.

Just watched an old Gardeners World and a young Monty, repot a Trachelospermum. ( easily found on Google). They don’t like root disturbance, but do like lots of water.

Great! I'll find that! I was watching him hack into the roots of a geum to make several plants the other night. Guess it's not flowering this year then 🙄

I have two, both from Aldi or Lidl (can't remember) and though they are both smaller than yours they are flowering well this year. They are in a bed, climbing up a trellis on an East facing fence. They do get morning sun and then the fence shades them from about 2/3 pm. I have never really pruned mine yet but I would day plant it out if you can.

*say not day! :/