You wouldn't need five or six climbers for that length, but it depends on how you're training them, and whether the site/soil can support them all. You'll need a reasonable amount of room for the other planting in front of any climbers, unless the soil and conditions are suitable enough for all of them to thrive. A clematis of 5m height would be a montana or similar, and you can certainly train horizontally. Once in situ, and well tied in, one of those would cover the whole distance, but if you want colour at different times, you could use two or three others instead, or a Group 3 somewhere along it to flower later. The smaller group ones will still cover a good width, and if you pick a Group 2 to go with that, it saves the pruning/tying in. They work the same way - flowering on the existing framework, so there's less tying in like you'd have with the Group 3s, which get cut back early in the year, so you'd need to tie those in as they grow. I have a macropetala which is planted near the back door, and continues along the fence for about 12 to 15 feet or so, and there's a Group 3 beyond that, which flowers in both directions, and at the other end, an alpina which covers a section of fence approx. 2metres by about the same in height. I had a Group 2 which flowered at the same time as the macro, but I lost that a couple of years ago. They were all perfectly happy together. They don't need much tying in as there's trellis and a cotoneaster for them to scramble though, and only one Group 3. I just guide stems occasionally into areas I want them. Just be aware that the larger flowered varieties need more food and water than the Group 1s. Can't help re roses as I don't grow them, but someone will advise with those. Did you mean you were putting a honeysuckle in there too? It won't be happy in such a hot dry sunny site, but it would cover the whole length if it was.
It's a place where beautiful isn't enough of a word....
I live in west central Scotland - not where that photo is...
Winter jasmine (J. nudiflorum) will easily fill the space on its own given a few years to do it (when a stem arches over and touches the ground, it roots and then puts up new stems). It doesn't twine or cling though, so it would need tying in to the trellis as it grew.
Doncaster, South Yorkshire. Soil type: sandy, well-drained
I don't think you need so many clematis to fill that wall. If you use this website search page - https://clematisontheweb.org/new-clemlistsearch.cfm - and enter group 3 in the Pruning Group box and/or viticella in the Group box you'll get plenty of options that will grow several metres high. Then you just have to choose your favourite colours and flower forms and check websites such as Hawthorne's, Priorswood, Taylor's and Thorncroft to see if they have them.
I've suggested Group 3 and viticella as these flower on new season's growth and are the easiest to control as, once established, they are hard pruned every spring. Then it's just a case of training in the new growth every spring so it spreads wide rather than just shooting straight up. You could alternatively do the pruning in late autumn then pull away all those old stems after they've wilted completely and thus minimise damage to roses or other climbers and allow access to prune those more easily.
You'll need to give the clematis a good mulch after pruning to protect their crowns and a generous feed of slow release clematis, rose or tomato fertiliser every spring. Planting close to a wall can mean they get very dry at the roots so be sure to water generously when planting and regularly thru dry spells.
Vendée - 20kms from Atlantic coast.
"The price good men (and women) pay for indifference to public affairs is to be ruled by evil men (and women)."
Thanks all - brilliant stuff. I've probably been too simplistic in trying to describe what I'm after - the "angel wing" thing I put up is just a random pic from the web. Here's a pic of one of the actual sites - lengthy trellis plus wall, with potential planting sites marked P. I'll probably plant 2 plants at each, idea of course being to try to get some interest throughout the year. I'm stringing wires alongside the trellis to help support the weight, and of course along the wall. It sounds as if most clematis (and likely J nudiflorum) can be trained horizontally with no problems, which is great! From some brief reading it sounds as if rambling (but possibly not climbing) roses may be trainable horizontally as well.
Hope that's vieweable; if not, in summary, S-facing, 4ft high, total length of c12.5m, planting points at c5m and c7.5m from left. The white lines/arrows are 5m lengths. A big (5m) clematis at the right hand side planting point sounds like it could be trained to reach left well past the tree and to the end of the wall on the right, which is great - what I was wondering is whether I can intermingle plants with different flowering periods (spring/winter/summer) to create all-year-round interest. Sounds plausible so far thanks to your help!
You can certainly plant something like pyracantha to provide evergreen foliage, spring blossom and autumn berries then a repeat flowering rambling or climbing rose - check sizes as they vary widely - but I'd stick to one group of clematis.
It's far easier to manage cultivation and pruning of clematis if they all get pruned at teh same time. Once a group 3 gets tangled up in a group 1 or 2 the latter will suffer when you prune and clear the group 3 growth. There are group 3s that flower for 3 to 4 months if well grown and look good intermingled with roses.
Vendée - 20kms from Atlantic coast.
"The price good men (and women) pay for indifference to public affairs is to be ruled by evil men (and women)."
Posts
A clematis of 5m height would be a montana or similar, and you can certainly train horizontally. Once in situ, and well tied in, one of those would cover the whole distance, but if you want colour at different times, you could use two or three others instead, or a Group 3 somewhere along it to flower later.
The smaller group ones will still cover a good width, and if you pick a Group 2 to go with that, it saves the pruning/tying in. They work the same way - flowering on the existing framework, so there's less tying in like you'd have with the Group 3s, which get cut back early in the year, so you'd need to tie those in as they grow.
I have a macropetala which is planted near the back door, and continues along the fence for about 12 to 15 feet or so, and there's a Group 3 beyond that, which flowers in both directions, and at the other end, an alpina which covers a section of fence approx. 2metres by about the same in height. I had a Group 2 which flowered at the same time as the macro, but I lost that a couple of years ago. They were all perfectly happy together. They don't need much tying in as there's trellis and a cotoneaster for them to scramble though, and only one Group 3. I just guide stems occasionally into areas I want them.
Just be aware that the larger flowered varieties need more food and water than the Group 1s.
Can't help re roses as I don't grow them, but someone will advise with those.
Did you mean you were putting a honeysuckle in there too? It won't be happy in such a hot dry sunny site, but it would cover the whole length if it was.
I live in west central Scotland - not where that photo is...
I've suggested Group 3 and viticella as these flower on new season's growth and are the easiest to control as, once established, they are hard pruned every spring. Then it's just a case of training in the new growth every spring so it spreads wide rather than just shooting straight up. You could alternatively do the pruning in late autumn then pull away all those old stems after they've wilted completely and thus minimise damage to roses or other climbers and allow access to prune those more easily.
You'll need to give the clematis a good mulch after pruning to protect their crowns and a generous feed of slow release clematis, rose or tomato fertiliser every spring. Planting close to a wall can mean they get very dry at the roots so be sure to water generously when planting and regularly thru dry spells.
It's far easier to manage cultivation and pruning of clematis if they all get pruned at teh same time. Once a group 3 gets tangled up in a group 1 or 2 the latter will suffer when you prune and clear the group 3 growth. There are group 3s that flower for 3 to 4 months if well grown and look good intermingled with roses.