That is a very vigorous type 3 clematis and at this time of year there is little you can do with training - the plant is at its peak of growth and will die back for the winter shortly. At the end of winter - around March - you should cut back the vine pretty hard, somewhere around 18" or to the third set of buds from the ground. From that point, training should be relatively easy! Growth can be fast - this gets to be a huge vine - so you need to keep on it. Stringing fishing line can help to give support but I've found the vine able to attach and drape itself over a fence or other structure quite easily without much assistance.

In my area, the rapidly growing, large species clems like SAC need no particular fertilizing - they grow fine without it. Just provide water during very dry periods and cut back hard each March. And you should be aware that this clem is considered to be invasive in some parts of the country due to its ability to reseed freely.

Thanks, that's very helpful. I'm not surprised it's sometimes considered invasive, I somehow got this one "free" - certainly didn't plant it. At least it's pretty. :)

I have posted this pic of my Clematis terniflora in another thread, but thought you may want to see what an outstanding vine it is.....
My vine is only 3 years old and covers my ugly chain link fence (about 15 feet)....

I've seen folks fasten wire fencing of some kind to a fence to help clematis climb.

Also, with regard to GG's comment about cutting it down, doing this annually will keep the blossoms from being only at the top of the plant, and it will grow to full height each year after the spring pruning.

I don't know where you are, but if you are in an area where it's warm enough for the seeds to ripen, trimming most of the old blooms off the plant with something like hedge shears after the bloom is done will help keep it from seeding around any more.

Ah thanks, that's very useful, I was wondering how to promote flowering. Also good to know how to help control re-seed.

I am virtually certain I've found the parent of my plant - a neighbor about 4 doors over has a beautiful one. I'm not complaining about my freebie, but something that spreads so readily does deserve close watching. ;)

Ian, that's a beautiful plant! Definitely improves the chain link.

My fence is wide, wide, wooden slats, and the poor plant *is* having trouble climbing it. I'm very antsy to start getting it put in order ... I tacked it up in one place, but because I let it go so long on its own it's a bit of a sprawling mess. Bought some twine and will make another go this weekend; will take some more pictures as I would like more advice. I understand it's the wrong time to prune, but it is such a tangly mess ...