Pruning Perennial Salvias
Salvias are popular all the world over. I’ve seen them growing in England, the Canary Islands, Mexico and in many different places here in the US. These plants are so versatile because they can comfortably fit into many styles of gardens from old fashioned cottage right up to modern simplistic. They grow well here in California where our Mediterranean climate suits them to a tee and they are loved because they have a long bloom time. Their non thirsty ways just plain make sense given our lack of rainfall for the last 3 years.
I was a professional gardener in the San Francisco Bay Area for over 15 years. This is where I first learned all about perennial salvias. The nursery where I worked in Berkeley sold many different species and varieties of them. This post is all about sharing what I know about pruning the two most popular types of perennial salvias which you probably have in your own garden. There’s a video at the end which you can watch if you like to learn by watching.
This is Salvia officinalis (with the lavender flower) or Culinary sage which is perennial here in Santa Barbara but an annual in colder climates. It is a semi-shrubby (or shrublet if you prefer to call it that), woody salvia which falls into the pruning category 1. It’s smaller than the greggi below so I would only cut it back by 6-8″ after flowering. Then, you can dry to leaves to use for cooking.
I’m going to talk about pruning them here in coastal California. You can tweak the process for your climate zone if they’re perennials where you live. The first type are the herbaceous salvias with woody stems. These are the shrubby salvias. A few which fall into this category that you may know are Salvia greggii (there are so many of these!), S. chamaedryoides, S. coccinea and S. microphylla. There are quite a few microphyllas too – the one you see in the video is “Hot Lips”. These you prune back after flowering but not all the way.
Above you see Salvia greggi which is a common landscape plant. It has woody stems & also falls in the 1st pruning category. I would take it down by at least a foot after each flowering cycle.
Take them back to at least where the first set of foliage starts on the flower stem – this could be a pinch or a You can take them down further if you’d like. I learned the hard way on an established plant to not cut it down to 3″. It never fully came back and out it came.
With these types of salvias I thin out what I want in the middle and then shape the plant so it’s pleasing to the eye. They usually go through 3 bloom cycles through out the year here. We have a long growing season. I would give them a mild pruning in the Fall and then a more intense one in the late Winter or early Spring if need be. There’s the whole Fall pruning versus Spring pruning debate. I personally like to leave plants with a little more substance over the Winter and then do the early Spring haircut and shaping.
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 will get extremely woody and won’t repeat bloom like you want them to. In my years working with salvias I found that some needed to be replaced before or around the 5 year mark. This is especially true with this type. Perennials don’t live forever after all. They tend to get straggly over time. No worries though because they grow fast especially if you purchase a 1 gallon plant.
This is Salvia leucantha or Mexican Bush Sage. They’re deciduous salvias with soft stems & fall into the 2nd pruning category. Once the stems have flowered & died off, cut them down to the ground.
Second up are the deciduous herbaceous salvias. The old growth eventually dies out and the fresh new growth emerges from the base of the base. They have softer stems which either die off and/or freeze. Plants that fall into this category are Salvia elegans, S. guaranitica, s. leucantha, s. waverley and s. patens. In the video you see me working on a Salvia leucantha or Mexican Bush Sage. These salvias are very simple to prune.
When it is 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 if you don’t but you’ll get more blooms and the plant will look 100% better if you do. Here in Santa Barbara the leucanthas and the Waverleys get huge. Many of them are not cut back leaving a tangle of dead twisted stems and they look like a ratty mess. Best to give them the shearing back they need. You’ll see the soft new growth appearing at the base. Another thing to know is that these salvias tend to spread as they grow so you might have to do a bit of dividing.
This is Salvia spathacea or Hummingbird sage which is also a deciduous perennial, pruning category 2. In the left foreground is the new growth. Cut the flower stalks (the old growth) in the back all the way down to the ground after they’re completely spent.
It’s best to know which kind of salvia you have before springing into action with the pruners. Both of these types of salvias really benefit from a good haircut. You’ll get much better bloom and shape if you do so. No ratty looking plants in my garden please! Do you have a favorite salvia?
In the video below you’ll see me pruning these two types of salvias. Enjoy!