For today’s post, I’ve been considering perennials offer flowers in red, white, or blue. After all, we’re celebrating the Fourth of July this weekend. The various ornamental salvias not only come in these patriotic colors but they’re ideally adapted to Colorado’s challenging conditions. That’s why I’ve made room for at least one salvia in my Colorado Springs garden.
Red salvias are landscape standouts. Some, such as Scarlet Sage (Salvia coccinea) are grown as annuals. Others are perennials, such as Texas native S. greggii ‘Furman’s Red’—a 2005 PlantSelect® winner that is hardy to zone 6. Its foliage may be evergreen in less-severe climates.
Currently, the hardiest red salvia I could find is ‘Vermilion Bluffs’ Mexican Sage (S. darcyi ‘Vermilion Bluffs’), another PlantSelect® winner (in 2007). The plants survive winters in the warmer parts of zone 5, and are thriving at Denver Botanic Gardens. Growing 3 feet and 4 feet high, ‘Vermilion Bluffs’ features brilliant red flowers that become the focal point of the late-summer garden. Plant in full sun in well-drained, un-amended soil; established plants need little irrigation.
All red salvias are irresistible to hummingbirds, and bloom from mid-summer—just when Rufous Hummingbirds are passing through. As an added bonus, the perennial plants tend to be resistant to deer and rabbits, and many are fragrant.
At first, it may seem odd to choose a plant native to southern Europe to represent “white” in our red, white, and blue line-up, but Silver Sage (Salvia argentea)is a most welcome emigrant. And aren’t we primarily a nation of emigrants? The plant is a biennial or short-lived perennial grown primarily for its rosettes of huge, fuzzy gray-white foliage (the species name, argentea, refers to the color silver). The second summer brings white flowers in spires up to 3 feet tall. Some gardeners remove the blooms in the hope that the plant will come back the following year to try again, but I treasure their almost luminescent white petals and unusual shape. No wonder Silver Sage is another PlantSelect® winner!
Once allowed to bloom, the plants will have completed their lifecycle. However, if the seedheads are allowed to mature, you may find volunteers come spring. Or you can carefully transplant any rooted offshoots that appear as the weather again warms.
Silver Sage is rated hardy to USDA zone 4a, so it has a good chance of surviving even a harsh winter. The plants grow best in full sun, and aren’t fussy about soil as long as it’s well-drained. Although they appreciate regular irrigation, they can handle some drought. As an added bonus, deer tend to avoid most salvias, although when it comes to deer, nothing is ever guaranteed.
When gardeners describe a flower as “blue” you can usually assume they mean purple. Many salvias are indeed purple; the cultivars ‘May Night’ and ‘May Queen’ are two of the most popular. Some are more of a periwinkle—a gorgeous blue-purple color I love to combine with yellow and orange.
But some salvias are what I call “true blue”—a gorgeous sky-blue hue rarely found in plants.
Blue Sage (Salvia azurea) is one example. Alternately called Prairie Sage or Pitcher Sage, it’s an American native hailing from Colorado eastward. Hardy in zones 4 through 8, this perennial does best in the back of the landscape, as it can reach 3 to 5 feet in height. The whorled spikes of azure flowers appear mid-summer to frost. Repeat bloom is encouraged by providing a bit more water.
The plants are easy to grow given full sun, fairly dry conditions, and average soil. Little maintenance is needed. If the plant gets too tall and floppy, cutting it back by half encourages bushiness. Otherwise, simply trim off the flower stalks as they fade, then remove dead leaves in late winter.
Blue sage is resistant to deer and rabbits, attracts bees, butterflies, and hummingbirds, and the flowers carry a lovely scent. With so many points to recommend it, we should be seeing more Blue Sage in years to come.