Pruning wild, shrubby sages is a bit of an art. They often grow very rapidly, developing woody stems that do not resprout reliably. It is recommended in Care and Maintenance of Southern California Native Gardens (available at RSABG and CNPS ) that you cut back these sages in the winter by about a third to a half when they are young. Once they have matured they should be pruned more lightly, taking care to avoid cutting back into the woody stems. Sounds simple but I must admit that this answer does not convey the difficulty I experience pruning my own sages.
I have three shrubby sages in my sidewalk garden that I’d like to discuss. The oldest is a rather odd hybrid that I got in 2004 at Rancho Santa Ana Botanic Garden. It is a cross between Salvia brandegei and S. munzii. Its leaves are narrow and it has a sort of upright but mounding habit; that is, it has upright woody stems but the new growth is on flexible stems that flow. This sage blooms during the winter and hosts hundreds of bees and butterflies. Furthermore, it makes the best tasting tea of any sage I’ve tried. However, the plant looks kind of – shall I say unkempt.
As with all of my sages, it grew very rapidly early on. I tried to keep up and prune hard in the fall (this one needed early pruning since it starts growing and blooming in December). As the years passed it developed the typical woody stems, but it also continued to grow rapidly each year. Maybe I was too timid and should have cut it back harder, but in the end it has a pretty bad structure. During the winter when it is in bloom it can look beautiful but by summer it looks disheveled. As mentioned above, I keep it for its early bloom, its appeal to bees and butterflies, and it wonderful flavor, but not for it overall beauty throughout the year.
The second sage that I have been working on is a cross between white sage (Salvia apiana) and black sage (Salvia mellifera) called S. ‘Starlight’. It too was cultivated at Rancho. Although this plant is much more upright, it is not a looker either. It has also been in the garden for more than six years and seems quite healthy. I doesn’t have showy flowers or a great taste. Maybe it should go!
And finally, I had great hopes for the black sage (Salvia mellifera) that I planted on the north end of the sidewalk garden next to the driveway. I am interested in using locally native plants and had hoped this would be a good choice. I planted it three years ago. Like the others I pruned it hard when it was young. It grows rapidly during the winter and I am being more aggressive, pinching the buds during winter.
A large black sage that grows by the entry of the South Pasadena Nature Park has looked good for many years. For several years a volunteer at the park adopted this plant, pruning more frequently than I would have. During those years the plant looked its best.
I think that the moral of the story is that sages can look great, especially when they are actively growing and blooming. Many do not look great during the summer and fall when they are dormant. Still, they smell wonderful and are loved by birds, butterflies, bees, and all sorts of other delightful critters.
As for my sages, upon reflection I think these are the reasons that I am not especially pleased with how they look.
- They are just standing alone with no rhyme or reason to where I placed them.
- Some get too much water since they are near non-native flowering trees that must be watered in the summer. This – and my rich, loamy soil – surely are responsible for their rampant growth.
- The black sage does not get full sun and will therefore probably be extra leggy.
- They need more pruning and pinching to keep them under control.
Let me know about your experiences with California wild sages.