Ah - wish you'd posted pics in the first place. The Oberon in the top picture is Oberon - the leaves indicate an evergreen clematis, quite different from deciduous types.

If the second picture is showing Vienneta, then that might well be what it is - the flowers already open appear to have green petal - now that may well be an environmental effect from the weather this year, or it might be actual Green Flower Disease, a disease that affects clematis, and you won't know till other flowers appear over time. And the presence of these green flowers with thickened petals might well be what they meant by 'rogue' flowers, although it would have been better if they'd explained themselves clearly.

Info here

https://www.rhs.org.uk/advice/profile?PID=349

Well, I've written to the nursery anyway and said I'm not happy so I'll see what response I have.

I wrote you a long PM then clicked the wrong button and deleted the lot! I'll try again later.

Well, the first pic is definitely of a C. cartmanii Fragrant Oberon, which is an evergreen spring-flowerer with leaves which are completely different to the summer-flowerers. No idea why you weren't aware of that when you bought it, unless the supplier posted a pic and description of something completely different...? And that supplier clearly wasn't Taylors, as their pic and description is clear. In any case, a quick internet search would have given you that information.

Regarding the Vienetta, which seems to be the one you bought from Taylors, I would wait now till its flowering season to see what happens with the flowers. Taylors is a highly-regarded nursery, so the chances of them having sent something which is disease-ridden and underfed are practically nil.

As I said on your other thread, you've had the plants since January, so the feeding regime was your responsibility. And regular liquid feeding every week or two from early spring to late May is the norm, not least with newly-planted youngsters. Chicken pellets aren't ideal as they're slow-release, and in any case, you weren't sure whether you'd pelleted or not.

'regular liquid feeding from early spring to late May is the norm?' it certainly isn't, rosierose, though it may be the norm for you personally, it's not the norm for everyone else.

I must have planted and grown a hundred clematis during my career in various gardens, and have never once carried out your particular regime, even with new plants. I certainly included fish blood and bone in the planting hole (except for plantings after July), but that's it. Not knocking what you do, but to say it's the norm isn't true. I've never even bothered to feed a clematis, other than a general topdressing in spring with growmore granules when the rest of the garden gets it anyway, and perhaps adding a mulch of well composted material, and apart from a couple of instances of wilt, and the odd year with green petal on early flowers, they've all been fine.

The nursery has agreed to refund me which is good news. The not so good news is that I have to dig up and return the plant. I asked what sort of packaging I should use, never having put plants in the post before. I also suggested that they pay the postage since the clematis wasn't performing as it should.

I have to wait for a reply.

Like you, Bamboo, I've never fed clems from spring onwards. They get a feed in Jan/Feb and then that's it and all have performed well for me.

You'll need a strong box, quite a tall one, and packing tape. Dig it up, put back in a pot, preferably the one it came in, insert a cane and tie the topgrowth to it, doubling it over if you have to so it's not too tall. Put the plant in the box, preferably with an extra piece of cardboard inserted underneath the pot in case the soil's wet, tape it with the packing tape to the bottom by using long lengths of tape across the top of the pot, down to the base of the box, so it's secured. Tape the box shut, punch a few airholes in the top and one of two round the sides with a skewer, mark it "fragile, live plant material" then send it.

When I had to return two plants, they sent a courier for it, but it wasn't Taylor's and the plants were healthy, they'd just sent me the wrong variety.

The actually packaging went long ago so finding a tall box might be a problem. The pot won't be and the rest of it I'd pretty much worked out. Thanks for the advice though, I'll see what I can find.