This category includes Salvia elegans, Salvia guaranitica Salvia leucantha, Salvia waverley, Salvia farinacea Salvia ulignosa, and Salvia patens.
With these salvias, the old-growth eventually dies out and the fresh new growth emerges from the base of the base. These types of salvias are better to prune in spring (in colder climates) because the old-growth will protect the fleshy new growth over the winter.
When these types of Salvias are through flowering, simply cut those stems all the way down to the ground. It needs to be done once or twice a year. They will still flower next season if you don’t, but you’ll get more blooms and the plant will look 100% better if you do.
Woody Stemmed Herbaceous Salvias
Type 2
Type 1
This category includes Salvia greggii (there are so many of these), Salvia chamaedryoides, Salvia coccinea, and Salvia microphylla.
You prune these salvias back after flowering but not all the way. Take them back to at least where the first set of foliage starts on the flower stem – this could be a pinch or you can take them down further if they need it. With these types of salvias, thin the stems out in the middle & then shape the plant so it’s pleasing to the eye.
Be sure to take out any growth which has died over the winter. If you don’t give these salvias some type of pruning, they’ll get extremely woody and won’t repeat bloom like you want them to. They get straggly and sparse – not a pretty sight in the garden.Perennials don’t live forever after all and may need to be replaced every 5 years.
Rossette FormingHerbaceous Salvias
Type 3
Type 1
This category includes: Salvia nemorosa, Salvia superba, Salvia penstemonoides.
These salvias form low rosettes, which are evergreen in coastal CA. The stems bearing more foliage and the flowers emerge out of them. In fall, prune the stems all the way down to the rosette and clean up any dead foliage growing close to the ground. The leaves tend to grow densely on this 1 so the undergrowth gets smothered.
The Bottom Line:It’s best to know which kind of salvia you have before springing into action with the pruners. All 3 types of perennial salvias really benefit from a good haircut. You’ll get much better flowering and shape if you do so.Whether you prune in fall or spring is up to you and the climate zone you live in.