How to Grow Clematis in Containers in the Frozen North P.2
2. Filling and Planting the container
We use a variety of materials to fill our containers. In the courtyard, a series of large, wooden boxes hold some pretty big clematis. (Said boxes were necessary because of the bumper crop of Very Big Rocks that were in the way...) These boxes are at least 18 inches deep and several feet across. Due to their large size, and the fact that they are built in place and will never be moved, we filled them with top quality loam we bought from a local farmer.
Smaller (whiskey barrel-size) containers are filled with a well drained potting soil that we use in the greenhouse. Whatever you use, make sure it is good quality - this is not a place to pinch pennies!
Once you've filled your container, follow our planting instructions
just like you were planting your new clematis right in the ground.