Stonecrop is a yellow-flowered plant found growing on dry, rocky slopes and outcropping. Right now at low elevation, it is at its peak in blooming. We have several species that are native to the Kootenays. You may find them all the way from the benchlands along the valley bottoms to the high alpine slopes and ridges. They bloom first at low elevations and as late as September at higher elevations. This tough little yellow star-shaped flower creates its own rock gardens.

Stonecrops are grown in many rock gardens; however, they are commonly called by their Latin name, sedum. For some reason or other, many people prefer sedum. Perhaps it sounds more intellectual than stonecrop or is just more becoming to the citizenry of some circles. After all, who would want stonecrops growing in their gardens? Stonecrop seems to me to be a bit more descriptive of its habit. It crops up around rocks. By either name, it is certainly not only easy to propagate, but easy to look after. It can go long periods with very little water.

Stonecrops are amazing plants. Their succulent leaves store moisture, enabling them to grow in extremely dry soil long after moistures from winter snow is gone. I recall once in a botany course, I collected a stonecrop and put it in the plant press. Amazingly, a month later, it bore a bright yellow bloom.

Another closely related plant with exquisite orange-red flowers, which in some books bears the Latin name sedum is roseroot. Anyone who finds this little gem growing in rocks and crevices on windswept slopes and ridges above 7,000 feet has discovered a treasure.

When the stonecrops bloom, parnassian butterflies are on the wing. Stonecrops are the primary, if not only, food plant of the caterpillars of one species of this butterfly. Stonecrop plants are only centimetres tall and often sprawl, and so the caterpillar may often be seen reaching up and feeding on the succulent leaves wile still on the ground. The black caterpillar amongst the green leaves or by the flower is an eye-catching contrast to the greenery and the bright yellow crown.

When seeking protective cover or when disturbed, the parnassius caterpillar will quickly scramble to hide in dry plant debris or under loose rock. It will also seek similar shelter when hibernating or when preparing to start the chrysalis stage. Because of the shortness of the growing season in alpine environs, the life cycle may take two years to complete. So, at high elevatioins, if the eggs are laid and hatch this summer, the caterpillar will grow for the remainder of this summer, all of next summer and the butterfly will hatch at the beginning of next summer. It is hard for me to imagine that parnassius caterpillars are waiting for summer to come while under five metres of snow. But that blanket keeps them, as well as many other plants, including stonecrops, and creatures, from freezing to death.

Stonecrop plants not only share their life above ground, but also below ground. Broomrape, also known as cancerroot, neither of which names I would say were delightful, parasitizes the roots of stonecrop. From that underground relationship, the one-flowered broomrape boasts a dainty yellow and purple trumpet-shaped flower. It has no leaves but gets most of its nourishment from the roots of stonecrop. Hence, you will often find stonecrop and broomrape growing in the same habitat. And there, of course, you can expect to find photogenic parnassius caterpillars or, in season, the beginning of summer, the adult parnassian butterflies. So don’t be afraid of contracting the photo bug and get out there and capture on your camera card some five-centimetre adults visiting stonecrops flowers or, later in the summer, some four-centimetre smooth black caterpillars decorated down the side with a row of yellow or red spots.

Ed McMackin is a biologist by profession but a naturalist and hiker by nature. He can be reached at 250-866-5747.