Spring and early summer blooming perennials and many annuals can use a haircut or close shave right about now (especially to clean up hail damage). If you're not sure, take a look at your salvia plants, they are the easiest plants to practice on. The flower heads are crispy and sending seeds everywhere, not that that's a bad thing. Re-seeders are easy to pull later or let them grow and fill up open space.
Does your plant look like this?
Salvia, along with catmint, blanket flower, coreoposis, cranesbill geranium and many more will re-bloom if regularly deadheaded or in the case of this salvia, taken down to the base of the plant. Once it's flopped open and finished blooming, nothing will help it re-bloom except a deep shearing. Or you can live with splayed plants for the rest of the summer until next spring after a long winter. Then remove the dead foliage as you do with spring clean-up. But that's a long time to wait for another flush of bloom and enjoyment. Cut it back now.
Below is what it looks like right after a heavy pruning, or what a long shouldered haircut would look like when cut to a bob length. Hair grows back quickly too, so in a few weeks this plant will be growing new locks!
Some perennials like peonies are once bloomers, nothing wrong with that, we enjoy their flowers then their foliage, which is lovely to view all season. Check this list of other common plants for additional tips on deadheading or cutting back. To Prune or Not to Prune
Another helpful article on summer perennial pruning Summer Pinching, Cutting Back and Deadheading
|There are actually five plants in this photo, all cut to the ground|