Traditionally, parkways have been inhabited by lawn grass, sometimes referred to as turf, of one sort or another. Though in recent years, as people have become conservation minded, water-thrifty plants have gradually taken the place of thirsty parkway turf.
With sidewalk on one side and asphalt on the other, both of which absorb heat and radiate it up and out to adjacent areas, parkways are definitely hot spots. And herein lies my fascination with parkway plants: Whatever grows well in a parkway can be relied upon to endure periods of dryness just about anywhere else.
The other day on Milbank Avenue in Sherman Oaks, between Hazeltine and Woodman avenues, I spied several plants performing admirably in parkway locations. Two of these plants were growing in combination with blue chalk sticks (Senecio serpens), a succulent ground cover with powder blue foliage that is almost everywhere these days. Blue chalk sticks appear to be the answer to the dreams of every gardener and garden designer who has been forever longing for a ground cover that holds its color throughout the year, is water thrifty, and exhibits unusual form as well.
Purpletop verbena (Verbena bonariensis), native to South America, is the perfect complement to blue chalk sticks. Growing up to 4 feet high, purpletop verbena blooms from spring until fall. It has a distinctively light and airy structure and is really nothing but stems and flowers, with foliage an inconsequential afterthought.
In rainier parts of the country, purpletop verbena has been found to be invasive due to its self-sowing proclivities, but I have found it to be utterly tame, despite occasional self-sowing in our own, rain-starved, semi-desert climate.
Rock purslane (Calandrinia spectabilis) is another South American native that stands up well in parkway plantings. Rock purslane is from Chile, whose climate is remarkably similar to California’s and for good reason.
If you look at a map, you will notice that Chile is the same distance south of the equator as California is north of it. You will also notice that Chile hugs the western edge of the South American continent, just as California hugs the western edge of North America. Each geographical region also has a mountain range — the Sierras here, the Andes there — that influences climate in a similar way. It is not surprising, then, that Chilean native plants grow easily in California.
Rock purslane bears its magenta pink flowers on 2-foot stems from now until November. Its succulent foliage trails along the ground and has an attractive, pale blue-green color. Once established, it only requires water once every two weeks, if even that. Like purpletop verbena, it is eminently suitable as a companion to blue chalk sticks.
One of the most fascinating horitcultural stories concerns the strawberry, with Chile and California playing significant roles in its telling. The strawberry that we take for granted on our supermarket shelves is a hybrid between strawberry plants carried back to Europe from the New World. French explorers in the 1700s brought back wild strawberries that they found growing in Chile (Fragaria chiloensis) and Virginia (Fragaria virginiana) to Parisian gardens. The cross-pollination between these two strawberry species, neither of which produces particularly large or sweet strawberries itself, yielded the giant, dessert quality strawberries we know today.
California happens to be the most hospitable climate in the world for commercial strawberry growing and is, by far, the biggest producer of strawberries, with 30 percent of the world’s production coming from this state.A brilliant yellow yarrow (Achillea ‘Moonshine’) is another Milbank Avenue beauty thriving in a parkway strip. Its finely cut, gray-green foliage contrasts wonderfully with its sunny, flat-topped inflorescences. Some herbalists consider yarrow to be the most medicinal plant in the world, with curative properties that extend to every organ of the body. Those who know how to utilize its infusions, its decoctions and its teas, swear by yarrow for treatment of headaches, flu, stomach disorders and a host of other ailments.Last week, I wrote about self-sowing plants that you might want to consider. Not long afterward, I bumped into a legion of annual larkspurs, blooming up a storm in Sherman Oaks. Larkspur is considered to be the poor annual sister of Delphinium, a closely related perennial that grows taller and with bigger flowers than larkspur.
However, in the interest of truth, it must be told that Delphinium is a magnet to snails and it seldom lives more than a year or two. Larkspur, by contrast, although it dies not long after its floral display ends, self-sows with zeal so that you can comfortably rely on its rebirth with a repeat, wall-to-wall flowering flourish the following spring.