Yes.

Agree. And the usual recommendation is to locate the crown of the plant 2-4 inches below the soil level or so the first set of leaf nodes is buried. This stimulates budding from the crown and results in the generation of multiple vining stems rather than just a single, (very skinny and fragile) one.

I do this with any size plant. For the very small starts or bare rooted clems, I pot them up for a full season, burying the crown as previously stated. I want them to develop a full root system before planting out and hopefully, to generate more basal stems. And then I bury them again when I plant them out the following spring.

IME, this helps the vines to establish more rapidly and be less prone to any mechanical stem damage (very common) and also less prone to any wilt disorder. I've grown scores of clematis over the years and I have never had an occurrence of wilt following these methods. I also prune them back hard the first couple of seasons, regardless of pruning group.

Thank you. Thanks gardengal! I ‘knew’ planting deep but your method makes clear why and how.. which I did not know. I will do this with my new clematis plantings.

It is my impression that this doesn’t apply to fibrous rooted plants such as C. alpina cultivars, but applies to just about all others. Is this correct or am I mistaken?

I am not aware that there are any exceptions to the 'deep planting' suggestion. And none of my clematis resources indicate that there are. Most are older texts to be sure (and British in origin) but still considered to be authoritative on the subject and ALL suggest the digging of an 18" by 18" enriched plantng hole and siting the plant so the root crown is well below the existing soil level. The exact depth differs a bit by source - several recommend 2-3" below the soil level; others suggest as much as 4-6 inches. But none specifiy taking a different approach for any of the different species (and I have never done so myself, either - every clem gets planted the same in my gardens).

The only thing they DO caution against is that those with the more fibrous root systems are more prone to root damage so disturb the roots as little as possible when planting. However, I was not aware of that caution until rather recently and have always treated all clems in the same manner when planting, including loosening and spreading out the root ball and I have never noticed any difference in establishment between the species and the hybrids.