clematis pruning - very confused!

BlueBirder

Hello again everyone, 

I'm hoping some of your wisdom might help me get on the right track with clematis pruning. 

I have two group 3 clematis (Etoile Violette and Forever Friends). I'm growing both horizontally along fences rather than upwards. They're both young plants - I put them in last spring. 

I know I'm supposed to prune group 3 clematis in late winter/early spring, to about 30cm above ground level. Both clematis (especially EV) have started growing shoots already, so I'm guessing now is the time.

The RHS website says that "Unless the plant already has three or four healthy stems growing from the base, all newly planted clematis should be pruned back hard the first spring after planting. Cut back to just above a strong pair of leaf buds about 30cm (1ft) above soil level." BUT despite new shoots higher up the plant, there's no sign so far of any new shoots in the first 30cm of last year's growth above the ground. 

Each clematis does have three plus stems already at ground level, but looking at the advice for more established plants it says "cut back all the old stems to the lowest pair of healthy buds 15-30cm (6in-1ft) above soil level". 

I'm not sure what to do, as it seems that the lowest buds are more like 50cm above the ground at the moment. I'm worried that if I cut back too far, there might not be any new growth at all later in the year.

Any advice would be much appreciated. Thank you!

Fairygirl

E. Violette is very easy - just cut it back to the lowest healthy buds. I lost F. Friends - too wet for it, but I'd do the same with it.
Did you plant them deeper than they were in the pots they came in? That helps new shoots form from below ground. You would do that with the bigger flowered types , ie Groups 2 and 3, not the early ones. 
It's beneficial to mulch them well too - that helps with moisture retention, soil health and structure, and also for that production of new stems.
 
When you say young plants, what do you mean? Good suppliers won't send out plants less than 2 years old, but if you bought them elsewhere, they'll be younger. Supermarkets etc often sell immature plants which can benefit from growing on for another year before planting out  

Busy-Lizzie

I have cut mine down to about 20cm, even the ones I planted last autumn. It encourages them to make new growth from the ground. It will also encourages any buds that are low down to break out. They have a habit of producing buds higher up then the low ones don't bother and the plant gets leggy looking with a lot of bare stem on the bottom part. You will be amazed at how much Etoile Violette grows in a season once it's a few years old.

Busy-Lizzie

PS. mine were 2 year old plants, chest high, not tiny ones from a supermarket.

BlueBirder

@Fairygirl and @Busy-Lizzie thank you for your replies! 

I did plant them deeper than they were in their nursery pots. They were from Thorncroft Clematis, so I guess this is going into their fourth year? 

I will cut them back to about 20cm then, and give them a mulch. 

Thank you so much! 

Busy-Lizzie

Thorncroft Clematis are good.

Fairygirl

They'll be fine then - Thorncroft is a highly regarded , reliable supplier. I've had several plants from them over the years   

LunarSea

Just wondering. If @BlueBirder is growing them as a 'fan', with the main stems horizontal, does he/she need to prune so severely? Will all the buds not eventually start to grow upwards from the horizontal and give the desired structure & coverage?

Busy-Lizzie

They aren't roses @LunarSea. Group 3 clematis get leggy bare lower stems and they flower best on new growth. They are usually vigorous growers.

LunarSea

Ok, but have you ever grown one with stems trained horizontally?

The OP stated quite clearly "I'm growing both horizontally along fences rather than upwards". With sap not rising in the usual way, would they still behave as you suggest?

Otherwise I stand corrected, and indeed I've just pruned a viticella in the accepted way   

Busy-Lizzie

Yes, I have as one of my fences isn't tall enough. But then I prune them. Once I didn't prune one on a tall trellis, had too much to do and I'd been away. It was a big tangle above and bare on the bottom. It did have lots of flowers though. So I suppose, to answer your question, I don't know (apart from what I have read) how they would behave if trained horizontally.