Q.How much can I trim back a Purple Sage?
I have a Purple Sage that has gotten out of control as far as height and width. Unfortunately, I’ve been cutting it like a tree which caused it to do this. I’d like to form it back into a bush, but wanted to find out if I can or if it’s too late. Can I trim it way back? I might be in trouble because the only part flowering are the ends and there aren’t many little branches on the branches anymore due to my cutting them off.

Now is not the right time for drastic pruning. This summer, remove faded flowers. 6 to 8 weeks before expected frost, trim off the top 1/3 being sure to leave several sets of intact leaves. This should help it bush out. In early spring, remove the 2 side branches, again making sure to leave several sets of leaves. Year 2, remove the center one. Another option is to take stem cuttings to start new plants. https://www.thespruce.com/pruning-woody-herbs-1402632