(News article for March 18, 2023; edited)
This week, I’ve continued to indulge my interest in reliably perennial herbaceous plants by writing about salvias.
Salvias are also known as sages and are members of the mint family (Lamiaceae). Many salvias bloom over an extended period between spring and fall. Like a lot of plants with showy flowers, most salvias put on the best show in full sun, though partial shade is often tolerated. Many support bees, butterflies, and/or hummingbirds with their nectar.
Some salvias tend to be perennial here, while others don’t. Species and variety selection are critical if you want one that’s likely to return.
Soil drainage also affects whether they survive from year to year. Most salvias are less likely to survive the winters on sites that tend to stay wet. Drainage may need to be improved if the site is not naturally well-drained.
LSU AgCenter highlighted five varieties during the Louisiana Super Plant program’s Summer of Salvias in 2022. Of those five, Orange Skyscraper, Rockin’ Blue Suede Shoes, Roman Red, and White Flame are more reliably perennial. Mystic Spires Blue Improved, on the other hand, may return after the winter but is not as likely to do so as the other four are.
Two other varieties in the Skyscraper series – Skyscraper Dark Purple and Skyscraper Pink – have also performed well.
A number of our more reliably perennial salvias are cultivars of anise sage (S. guaranitica) or hybrids that have this species in their backgrounds. Such varieties include Amante, Amistad, Argentine Skies, Black & Bloom, Black & Blue, Blue Ensign, Purple & Bloom, Rhythm & Blues, and Van Remsen.
While the names of many of these suggest the color of their flowers, Amante, Amistad, Argentine Skies, and Van Remsen aren’t giveaways. Flowers of these have been described as fuchsia, purple, sky-blue, and blue, respectively.
Mealycup sage (S. farinacea) is native to the south-central US. Not all cultivars of this species are reliably perennial in Louisiana, but several have performed well. Among these, Henry Duelberg and Rebel Child have purplish blue flowers, while those of Augusta Duelberg are white.
Scarlet or blood sage (S. coccinea) is a red-flowered southeastern US native. It’s perennial and also seeds itself freely. You’ll likely find seedlings coming up around the original plant.
Another native, lyreleaf sage (S. lyrata), is often seen growing as a wildflower or weed – depending on your perspective – in early spring. Flowers are spikes with light blue, lavender, or white petals.
Mexican bush sage (S. leucantha; purple and white flowers, typically) and forsythia sage (S. madrensis; yellow flowers) can perennialize if given excellent drainage. These flower in the fall.
While most salvias need well-drained soil, bog sage (S. uliginosa) can grow in relatively wet areas. It produces elongated spikes of light blue flowers. Bog sage grows to approximately four feet tall and will spread.
You may be wondering about culinary or common sage (S. officinalis). This herb is plenty cold hardy for Louisiana but needs excellent drainage – it’s probably best to grow it in a container – and, even under good conditions, it may need to be replaced every few years. Incidentally, rosemary (S. rosmarinus) was reclassified as a salvia several years ago, having formerly been Rosmarinus officinalis. This perennial herb needs well-drained soil like most salvias do but isn’t as finicky as culinary sage is.
Let me know if you have questions.
Contact Mary Helen Ferguson.
'Purple & Bloom' hybrid salvia. Like many salvias that tend to be perennial here, this one has anise sage (Salvia guaranitica) in its genetic background. (Photo by M.H. Ferguson)
'Henry Duelberg' mealycup sage (Salvia farinacea) (Photo by M.H. Ferguson)