Hydrangea shrubs have enough room underneath, that you can make a beautiful layered garden by underplanting them with shorter plants. In summer I have some dwarf Campanula (bellflowers) producing purplish blue star shaped flowers in a low carpet under this Hydrangea paniculata. I love the look, and wanted to extend it to spring, so I’ve planted some Chionodoxa forbesii (glory of the snow) bulbs underneath. These early spring bulbs should flower before the bellflowers bloom, with their own version of starry flowers.
Above is a photo of Campanula poscharskyana (Serbian bellflower) from this summer. They start flowering midway through June, and continue intermittently all summer, and into fall. They look especially pretty under the Hydrangea, even before it flowers, twinkling up through the branches. They are a gorgeous shade of purplish blue, with five narrow petals and white towards the centre. These bellflowers grows quite low to the ground, so they don’t interfere with the Hydrangea branches, and they fill the bare area underneath with beauty. Then in August and September, when the Hydrangea blooms in white, the little blue flowers of the Campanula look lovely paired with the large panicles. However, there are no flowers underneath the shrub before mid June, just the bellflower foliage.
I added some glory of the snow bulbs to bring some early blooms to this area. The blue stars are reminiscent of the Campanula and should have a similar effect. These have six petals, a dark line down each petal, and a white centre. The Chionodoxa luciliae start flowering during May in my zone 3 garden, so the Chionodoxa forbesii should start the colour show early too, before the bellflowers. These two Chionodoxa species seem interchangeable now. The pretty blue bulbs will bring some spring cheer, while the Hydrangea stems are still leafless. Then when the glory of the snow flowers fade, the bellflower groundcover should easily hide the slender bulb foliage as it dies back for the season. Usually the Chionodoxa foliage disappears quickly.
Here is one of the bulb planting holes, in between the Campanula poscharskyana plants. I dug narrow holes among the perennials, to minimize the root damage. Then I planted 5 to 10 bulbs in each hole. Altogether I planted 50 Chionodoxa forbesii, but I could have planted more. These bulbs cover the ground under the front half of the Hydrangea, and a bit around the sides. I could plant another 50 to really carpet the ground under the PG Hydrangea.
The fall leaves were already covering the garden bed, as I watered in the newly planted bulbs. This will be some of my last outdoor gardening fun for the year, since the temperatures are so cool now. It is probably a little late to be planting bulbs in zone 3, but the weather warmed above freezing this week, the bulbs were on sale, and the picture of more blue flowers was running through my mind. Soon, a white quilt will be spread over top of the brown and green patchwork one. However, come spring, the flower parade will start as soon as the snow melts, and the early spring bulbs bloom.