Cool roots are a bit of a myth. Consistent moisture is more important for clematis IME, so some living or organic mulch works well.

Does it need to be moved? Or do you prefer it in the new site? I've planted and moved clematis both spring and fall successfully. It will have a large root ball, so be prepared to do a lot of digging, both for removal and to create a large hole in the new spot ahead of time (or a quite large pot) and be ready with a way to move it such as a plastic garbage can lid or or snow saucer since it will be heavy.

If it doesn't need to be moved, planting a new clematis in the new site might be easier. Then you would have more clematis to enjoy!

Right now, it's technically planted in the grass, then trained up over 2 steps and to a pergola (I am the same person who posted about removing my non-performing wisteria in the Vines forum).

It will be moved about a foot, but the riser for the steps is in between. Being in the grass, it’s hard to trim around (technically, we don’t very often) and more vulnerable to rabbits
chewing the bark in the winter.

Fall would have some advantage to me I can do it while doing the construction, while in spring there is always so much to do.

Should I wait til its done blooming? Given that it’s not going far, actually closer to its support, I don’t even need to cut down the vines.

Given its young age of 4, how big a root ball should I expect? Just want to know where to put the garden fork down through the grass. That will be a bit more challenging ferreting around for roots, than digging up something in a garden bed.

Big vines have big root systems so figure size to move by the size of the vine. And since this vine should be hard pruned anyway, I wouldn't even blink at cutting it back almost to the ground before you tried this. It will be much easier to handle if cut back and will sustain far less damage.

Thanks! It just seemed really harsh to cut it off while blooming. I must be a softie!

Normally the hard pruning should be done in the spring, though, right? It's funny, I pruned my 3 other ones this spring but always forget to do this one.

Fall or spring (late winter) - your choice.

I often get to pruning the others a little too late in the spring. Then feel bad when chopping vines with sprouts. It would be much easier to yank down all the dead vines in fall.

Hard pruning is : down to like a foot above the ground?

Which classes get hard pruning? I have two type 3's and a type 2. I didn't know where SAC belonged before.I had a site bookmarked but it's now a dead link. I need to figure out what my 2 newest ones are.

Hard pruning for me is down to a set of buds or two per stem, but I am not exact about it. I take a look, figure out where to chop to leave a couple buds per stem, and then it gets a couple of whacks with old-fashioned hand hedge clippers and old top growth is composted. Easy. Type 3 is hard prune, but here in the frozen north, Ma Nature often prunes type 2's down to the snow line, so I usually just whack those back as well if they are near the type 3's. They do fine, but just bloom a bit later, which is fine with me, and that way I don't need to remember which is type 2 and which type 3. If you haven't already pruned the type 2's with the type 3's, you can prune lightly after they bloom to see if you can get a second bloom from them. My season is short enough that the ones I leave over winter and then lightly prune still don't rebloom, so it doesn't make much difference for me. I know one grower in southern OH who prunes back many of her clems after their first bloom (including type 3's) and gets another bloom from them around now, but it isn't necessary, just tidier.

So the short story is, as long as you don't have a type 1 (montana or macropetala/alpina/atragene), which bloom in early spring, you can hard prune them all.

The pruning guidelines revolve around flowering time. If you know when exactly your vine blooms, you can make informed assumptions about how to prune without even being able to identify the species or cultivar!!

Type 1's are the no prune or prune immediately after flowering vines. These are very early flowering vines (typically late winter to early spring) that flower on old growth and are almost always species clematis.

Type 2's are light pruning vines. This category includes nearly all of the large flowered hybrids, with bloom times from mid spring through late summer. These vines tend to bloom on both old and new growth, which is why many will have a later but lighter repeat flowering.

Type 3's are late flowering vines, blooming from midsummer into fall. These bloom on growth produced the current season and are very often quite large vines when mature. They can (and usually should) be hard pruned as Bab's described.

I tend to simplify pruning by limiting it to those I prune hard and those I don't prune at all. So all type 1's get NO pruning unless they simply outgrow their space (then prune immediately after the flowering) and ALL others get hard pruned at some point during the winter months, as new growth begin early in my area.

If you don't get around to pruning in a very timely manner (weather, etc.), do not be afraid to do so later than what is advised :-) When I had my big garden with scores of different clems, I sometimes missed pruning all when I should and often cut back vines with a lot of new growth showing, sometimes even with tiny flower buds present. If the plant is not dormant, pruning will actually stimulate new growth and the vine will respond by pushing a lot of new growth and buds. It may just bloom slightly later than typical.

FWIW, commercial growers prune their vines back repeatedly during the growing season just for ease of care (reduces tangling, etc.) and the vines (2's and 3's) will still produce flowers.

Thank you both! From now on, I hard prune in the fall :) I don't have any type ones... not yet!

I have found when transplanting large clematis that the root system may fall apart producing several new plants.

I also hard prune most of my type 2 and type 3 vines in the late fall to get rid of the dried vines. The exceptions are the type 2 s that open with double blossoms with the first spring bloom. Even those usually die by to the ground with our winters but winters are becoming more mild here so some of those vines survive with buds and get pruned in the spring as far along the old growth as possible.

Seriously can you avoid doing that until it goes dormant? I guess you can, is there a nursery nearby you can ask? We have a wonderful horticulturist down at our nursery and she knows everything. Right in the middle of blooming I suppose if you have to, but those things are rooted everywhere depending on their age. If it's gigantic, good luck with that. If it's just a couple years old you can try transplanting it like that rose guy does it. Paul Zimmerman on Transplanting a Rose in Season. He uses a spade and a shovel and sandwiches the plant in between them both and picks it up. You should watch it on youtube before you even try it. He's done it thousands of times. I would not want to do it. He works for Jackson Perkins and I love his videos. Good question though

My husband was rebuilding the deck around where this was coming out, and didn't want to wait. So I went ahead and did it. After soaking a couple of days in a row, I dug it up with no difficulty. Root ball was about 8", if I recall. Because it was only going a foot, but on the other side of the wood stair riser for the deck, I did not need to cut down the vines.

I do not think it made it, though. Unless it comes up from the ground. I went out to prune a couple of things 2 days ago and cut it off at the 1 foot level, and saw no green under the bark.

If it IS dead, I will replace it with something else. Though I like the starry white flowers, they always did all their blooming on top of the pergola, where they could not be seen unless I wanted to look out of an upstairs bedroom window. :( I will go for a honeysuckle instead.

An 8" root ball is very tiny for a 4 y.o. clematis and especially so for one that grows as large as SAC!! I think you probably missed a lot of roots, which would certainly impact how well the vine responds in its new location. I wouldn't give up on it quite yet :-) These are much tougher plants than many suspect and display a very strong will to survive.

I once dug up an established C. armandii, a vine of similar size and robustness, and it took me several days to do so. The root ball was more than 2' across and 2' deep and with several roots as big around as my wrist. It was a monster!!