Information Possibly Outdated
The information presented on this page was originally released on March 9, 2006. It may not be outdated, but please search our site for more current information. If you plan to quote or reference this information in a publication, please check with the Extension specialist or author before proceeding.
Mystic Spires Blue is a hot perennial salvia
By Norman Winter
Central Mississippi Research & Extension Center
Since its discovery almost 40 years ago, Indigo Spires salvia has been one of the most loved flowers in Southern gardens. It deserves the Mississippi Medallion honor even though it has never received the award.
This preserving perennial was found growing in the Huntington Botanical Garden in the 1970s and was made available in 1979. John MacGregor, horticulturist at the California garden, described his lucky find as a "sterile hybrid, courtesy of the bees." He named it Indigo Spires.
One of my favorite horticultural Web sites says, “Indigo Spires tends to keep growing and growing and then falling over under its own weight. Constant pruning and pinching will keep it in bounds, and removing the flower spikes after most of the flowers have dropped off will encourage more blooming.”
This is precisely what we do at Mississippi State University's Truck Crops Experiment Station in Crystal Springs every year to have it looking good for the Fall Flower and Garden Fest in October.
This spring, BallFlora Plant will introduce Mystic Spires Blue, the first dwarf or compact selection of Indigo Spires. Preliminary reports suggest it will grow 12 to 14 inches tall, but I suspect 18 to 24 is more likely. The old Indigo Spires typically reached 36 to 60 inches in height.
If winter drainage is good, Mystic Spires Blue will be cold hardy through zone 7, like its predecessor. While we normally think about drainage in the spring and summer, it is most important in the winter for salvias.
We had over 6 inches of rain in January and another healthy dose in February. Wet winter feet spells doom for salvias, lantanas and verbenas, but good winter drainage coupled with mulch will allow many plants to return in the spring far outside their hardiness zone. The parents of the original Indigo Spires are Salvia farinacea and Salvia longispicata, both from Mexico, so they are very tough and drought tolerant.
Plant your Mystic Spires Blue in full sun in well-drained, well-prepared soil. They will work well with perennials like purple coneflowers and summer phlox, or combined with yellows like melampodium, black-eyed Susans and New Gold lantana. Try it with the new Lucky Pot of Gold lantana, a more upright version, and the Mississippi Medallion award-winning Sonset with its yellow, red, orange and magenta colors.
Mystic Spires fits perfectly in the backyard wildlife habitat attracting butterflies, bees and hummingbirds. Salvias are among the easiest and showiest of flowers for the garden. Plant these if you want to garden and golf or play tennis.