Ignite some fall fireworks by including Salvia leucantha in your planting beds. Also known as Mexican bush sage, Salvia leucantha explodes with bright color in late autumn. The plants offer handsome, woolly leaves through spring and summer, and when fall flower spikes appear, Mexican bush sage’s wow factor surfaces.
Salvia leucantha opens traditional salvia-style flowers. The individual blooms emerge along spikes, and the base of each blossom is held inside a colorful cup-like structure known as a calyx. The calyx on Mexican bush sage is fuzzy and brilliant purple, glowing in the fall landscape. The actual flower on Salvia leucantha is white, and there are only ever a few blooms open at once on a flower spike. As blossoms fade, purple bracts linger and steal the spotlight.
This sage grows into a substantial shrub-like plant, reaching 36 to 48 inches tall and wide by the end of the growing season. Leaves are long and pointed, with a somewhat puckering, olive-green on top and white and woolly underneath. Stems on the plant also have that same woolly white appearance, which is attractive in the garden as the plant grows through the summer months.
The flower show on Salvia leucantha starts in very late summer or early fall. Purple bracts appear first and linger until frost. The stems of fuzzy purple bracts make great additions to dried flower arrangements, adding color and texture.
Give Mexican bush sage a spot in full sun for best growth, even in hot southern zones. This plant is hardy in Zones 7b to 10 and thrives on heat. In northern gardens, it’s grown as an annual. Average, well-drained soil gives Salvia leucantha what it needs to thrive. In zones where it’s hardy, soil must drain well in winter. Wet winter soil will quickly kill Mexican bush sage. The secret to overwintering Salvia leucantha in Zone 7 is dry winter soil.
Plant Mexican bush sage in spring in warm zones; wait until all danger of frost has passed in coldest regions. If you garden where Salvia leucantha is hardy, get it in the ground in spring so it can establish a substantial root system before winter chill arrives. In warmest zones, Mexican bush sage can retain purple flower bracts and continue to add color to scenery through winter into spring. Frost is what stops the flower show.
Salvia leucantha benefits from pruning at several points in the year. In regions where it’s hardy, cut back previous year’s growth in spring. In Zones 7 to 8, if cold weather killed top growth, cut plants back to soil level. In early summer in warm regions, prune plants to remove one-third of growth to shorten the final flowering height and limit flopping stems. Do not prune plants in northern regions where Mexican bush sage is grown as an annual. Pruning in these regions risks delaying flowering, which might mean no flowers if an early fall frost occurs.
Use Mexican bush sage in butterfly gardens—both butterflies and hummingbirds flock to it when it blooms in fall. It works well paired with butterfly bush or autumn sage (Salvia greggii).