Dear woofie, I put the cuttings in deep pots and sink them into the soil! This is because I don't want too many of them! I have one in the back garden and one in the front so people are always stopping to admire them and want one.
The good thing about gardeners the world over is their kindness to share both knowledge and plants. As passion vines are easy to grow here I simply give them away to people who ask for one, well rooted in a deep pot, and most have no trouble with them in this area! I have a small walled garden which keeps warm and a wooden fenced garden as well, but they grow in both and it does get down to -20 F here.
Once they and the evergreen Clematis with its heavenly spring and autumn scent get established, I mulch them well. This keeps the frost out, as we can get frost till late April. Hence why our Asparagus season is the last two weeks in May and the first two weeks in June.
Regards.
Neil.
