Knowing how to prune sage plants properly will help them last for years, so you can continue to brighten your garden borders and welcome pollinators summer after summer.
Pruning them every now and then is great to keep them compact rather than leggy, and can also encourage more flowers. Doing so at the right time is crucial to helping them survive the cold of winter.
It’s an essential part of successfully growing sage, and it’s not hard to do, once you know how. To help you get started, experts share their tips on these woody shrubs.
When and how should you cut back salvias?
“You need to prune twice a year, to promote a dense, attractive growth habit,” says William Dyson, who runs a specialist salvia nursery. He recommends pruning fairly aggressively in early to mid-spring, and removing dead wood.
John has been a garden journalist for over 50 years and regularly answers reader questions for Amateur Gardening magazine, including many about sage. He also wrote four books and gave many lectures on gardening.
John Negus agrees, and recommends cutting plants back to within 18 inches of the base in the spring. He adds that he followed this up by feeding them fish, blood and bones, repeating the requests monthly until early fall. “The latent buds around the trunks will bloom within three or four weeks and create a well-balanced shrub.”
A second, lighter pruning is recommended in mid-summer, as a cross or wild cut returns a pair of dead leaves and flowers. “Not only does this encourage a tidy frame of branches and prevent the bushes from becoming sparse, but it also removes spent flowers from the early flush of bloom, promoting another great flush,” says William.
In the fall, when the sage plant’s display is over, don’t be tempted to cut it back — the top growth will help protect the crowns from cold weather, says John. He adds: Apply a thick layer of mulch, then wait until spring to prune again.
Most important tip: “If you’re trimming thick stems—those larger than 0.5 inches in diameter—smear the cutting with Vaseline to retain moisture,” John advises. Anvil pruning shears, like these from Amazon, create cleaner cuts on these wood materials.
How long do salvia plants last?
Learning how to prune sage plants will help increase their lifespan, which can exceed ten years with the right growing conditions. The ‘Lemon Pie’ plant that she prunes back hard every spring has lasted 20 years through many cold, wet winters, says Anne Swithinbank, an expert gardener and garden writer.
However, hardiness varies between varieties, so in colder regions, it’s best to take cuttings from plants as a backup, adds Anne. She suggests doing this in mid- to late summer, taking 3-4 inch heel cuttings or shoot tips.
How should you deal with leggy sage?
Leggy growth can be the result of neglecting sedge pruning, but it can also occur if it is growing in the shade and does not receive enough light to ensure full growth. If it’s the latter, you may want to move it to a more open, sunny location, says John Negus Amateur gardening. “If you think it would benefit from being planted elsewhere, treat it in early spring, provided the soil is crumbly and drains freely. If not, wait until it is suitable for digging.
“Make sure you lift them with as much soil around their roots as possible,” he adds.
“They can then be pruned later in the spring when they have re-established,” he continues. To do this, shorten the stems by at least half their length.
Should you prune annual sage?
You do not need to prune annual varieties of salvia, because they complete their lifespan within one year. Simply dig them up and place them in the compost bin at the end of fall once they have finished flowering.