What's Blooming: The Rock Garden

Clematis and pasque flowers blooming in the Rock Garden

What’s Blooming: The Rock Garden

by Bryan Fischer, Horticulturist, Gardens on Spring Creek

Heralding the opener for a slow, cool spring, the Rock Garden is finally coming into bloom. Wet, cool snows and frigid temperature plunges this spring have kept many plants from breaking dormancy and have slowed the bud development of others. In fact, many plants on our grounds are almost two weeks behind their normal bloom times.

This aside, the spring is shaping up to be a great one for the diversity of blooming plants on our grounds. Members of the Ranunculaceae seem to have particularly enjoyed the chilly weather, with pasque flowers (Pulsatilla spp.) of several species reveling in the weather conditions more reminiscent of their mountain origins than our occasional jumps to 80 degrees or higher the way our last few springs have been.

Pulsatilla vulgaris, or common pasque flowers in bloom

Pulsatilla vulgaris, or common pasque, is the most visible of these on the grounds. Self-seeding liberally around the Rock Garden, particularly on east-facing aspects, the species is producing swaths of two- to three-inch royal purple blooms with yellow centers consisting of dozens of fuzzy anthers. Though not native, this species is arguably the easiest to grow in the genus, as it tolerates transplant better than many of its near relatives.

Clematis hirsutissima var. scottii

One near relative that does transplant reasonably well, albeit slow to establish from transplant, is our native Clematis hirsutissima, as well as it’s variation, Clematis hirsutissima var. scottii. Commonly called sugarbowls or Scott’s sugarbowls, these native clematis form neat two-foot mounds rather than the large, ungainly vines we often associate with this genus. These plants’ fuzzy, finely-cut foliage is breaking ground in many cooler places of the Rock Garden now, and the blooms of these plants are already popping on the garden’s warmer aspects. Velvety, nodding flowers that mirror those of pasque flowers in shape but hang over these plants by the dozen give the plants a quirky, yet surprisingly polished look. Clematis hirsutissima offers more finely-textured foliage and a slightly earlier bloom, and the foliage of C. hirsutissima var. scottii is less hairy.

Clematis seedhead

One of the most appealing features of these unique clematis are their seedheads, which look a bit like truffula trees from the Dr. Seuss book “The Lorax”. Appearing with one inch long, fuzzy tails in dense clusters at the top of each flower stalk, the seedheads of these plants glow with backlighting in the morning and the evening. I aim to site these plants where they will receive east or west lighting, so as to take advantage of this trait and maximize seasonal interest.

Expect to find these blooms for the next three weeks in the Rock Garden, with seedheads lasting for weeks more.

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