I asked Carolyn if she had anything she would like to add:
"I built the bench of spruce limbs and poplar boards. The planting box is lined with pond liner, then a layer of coco mat for drainage. The soil is lean and sandy, as soil that is too rich makes lush and lanky growth. The whole structure is 7 feet tall, 6 feet wide, and 2 feet deep. Last summer was quite dry, so I had to keep it watered; but my intention is to have it "self-sufficient"."
"I first saw and read about green roofs on the internet, then bought a book to read about the subject. I know that there are sod roofs here in Alberta, but have never heard of one with perennials. So I really wanted to give one a try. I planted with assorted perennials and a few annuals for colour: Bearberry, blue flax, alpine poppies, Alpicola primulas, hens & chicks, alpine columbine, species tulips, squill, nemesia & dwarf phlox (annuals). "
"It is just coming through its first winter, so will soon see what has survived! If nothing else, I will just plant it to drought-tolerant annuals every year. I will report on survival rates of the different plants as soon as I know."
Carolyn Rallison
Last West Gardens
Bluffton, Alberta
Zone 3