Hi, just saw your message and thought I would write a response. So, I have rooted Jackmanii and also Tiaga . I am in the process of doing more Jackmanii and an unknown pink and now Dr. Rupal . What I have done is trim back the clematis to the height I want or what is recommended. I wait until the plant is starting to put out some new growth. Then I bring in the cuttings and trim them and take multiple cuttings of about 5 or 6 inches so that each cutting has a stalk and then a node with a set of new growth on each . I set in water for a few days so that the cutting can take up some water and then I lightly scrape the outer 3/4 inch or so of the bottom part of the stalk so that some of the green underneath is showing and then I prep a recycled water bottle with dampened soil to plant the cutting in . These provide a humidity dome for the cuttings . I make holes in the soil and drop the rooting hormone covered cutting into each hole and firm it in . I can fit about 5 comfortably in the bottles I use. I keep in a warm place with NO direct sun and let them do their thing . Not all survive but plenty do . Hope this is of some help and that you have some success in rooting your cuttings !!! It is a thrill to be able to increase your plants this way.