Nancy, that would depend on which salvias you have. I'm not going to comment on pruning schedules from across the country in a much cold zone, but your salvia growing neighbors are going to need more information.

I did a search:

This was under Westelle's post pruning salvias:

Posted by: Rich_Dufresne z7 NC (My Page) on Tue, Jan 25, 05 at 21:07

Please wait until you see new growth. I use the `asparagus' rule to trim Salvias. Bending the stem until it snaps (towards the outer end) will reveal the approximate area where the transition of the woody growth to new green growth is. This is also the point where cuttings are taken.
I treat shrubby woody stemmed sages like greggiis and microphyllas that form twiggy, woody growth like raspberries or roses. Definitely do not cut these to the ground.

Cutting to the ground is only good for those sages that form short stolons underground and send up new shoots, like sinaloensis, glechomiifolia, leucanthas, some microphyllas, guaraniticas, and others. If the plant was rooted and set into the ground with no nodes beneath the soil line, it will not send up shoots in any case. You can often tell this has happened when there is a thick trunk coming from the soil, and the first node has a multitude of stems coming from it. Cut that boy off, and you have a dead plant.

Westelle: Thank you Thank you Thank you!!!! I very much appreciate the work you did. I didn't know how to look it up and was at my wits end. Nancy

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