How To Prune Old World Salvia
- These Salvias are deciduous. Leave their frost-killed foliage on the plants over the winter months. Many beneficial insects use the old foliage and stems as protective cover over the winter.
- Cut them back to an inch or two above ground in early to mid-spring.
How To Prune Native Salvia
These plants are variable in how they like to be pruned.
Salvia greggii cultivars and hybrids, such as like Raspberry Delight®, 'FlowerKisser® Royal Rose', 'FlowerKisser® Dark Shadows', 'FlowerKisser® Coral-Pink', ‘Furman’s Red’, ‘Cold Hardy Pink’, ‘Ultra Violet’, and other shrubby sages:
NEVER cut back shrubby sages in the fall. This often results in winter die-back.
- Leave them standing over the winter and prune moderately in mid-spring when the new foliage begins to push from the woody stems.
- Trim back to just above green leaves to shape the plants and remove old flowering stems. Thin out dead or weak branches in the center of the plant.
Other native Salvias, including Salvia azurea, Salvia reptans 'Autumn Sapphire®', ‘Maraschino’, Salvia uliginosa, ‘Limelight.’ and others:
- These Salvias are deciduous. As with Old World Salvias, leave their stems standing over the winter months.
- Prune them back 2 or 3 inches above the crown in mid-spring, when the new foliage begins to push from the base of the plant.
Evergreen native species, like Salvia dorrii and Salvia pachyphylla:
- These Salvias hold their foliage over the winter
- Only trim in mid-spring to remove any winter-killed branch tips.
- Deadhead after flowering is finished.
When growing native Salvia in colder regions at the edge of their cold hardiness (zones 5 & 6), extra winter protection will prevent winter-kill of young plants. These native Salva take a couple of growing seasons to mature and reach their full cold hardiness. To prevent winter-kill:
- DO NOT cut them back in the fall.
Provide some insulation over the crown and lower branches. I recommend using long pine needles or clean straw to cover the plant under a foot-deep pile of these insulating materials in late fall. Uncover the plant(s) in early to mid-spring. Then after the new growth pushes from the stems, prune as needed.