Deadheading Flowers

When you first hear the garden term ‘deadhead’, you might picture friends who wore tie-dye and traveled to concerts a lot.

But gardeners use the term deadhead in a completely different way. Deadheading keeps gardens neat and blooming. It’s a form of good plant housekeeping.

You can get by without it, but your garden will give you extra ‘oh’s and ah’s’ if you prune, pinch and deadhead a bit. Yes, it sounds a little, assertive, right? But plants - like all of us - need boundaries. Proper plant pinching gives our herbaceous buddies just that, while keeping our gardens looking their best.

Basically, deadheading means the removal of flowers that have already put on their show. But should you cut back all perennial flowers? Are there some flowers that pop again nicely after a good shearing? Is there a reason NOT to remove a spent flower? Yes and maybe can answer each of those questions.

Horticulturalist Wendy Brister said plants respond to pruning to perpetuate their species.
“With many plants you get re-bloom when you deadhead since, basically, the goal of the plant is to grow, set seed and die,” said Brister, “So if you take the spent flowers away and prevent it from setting seed, it will set new flowers and keep trying to produce seed before it ‘dies’.”

“Salvia is one to cut back after the first round of bloom. Shear all the spent flowers off for a great second show,” said Brister.

With some plants, like hardy geranium or coreopsis, it might seem a daunting task to remove all the small flowers. In that case, shearing the plants with a long bladed hedge shear works really well. With other plants, scissors or pruners are the way to go.

Brister said you should carefully choose places to cut when deadheading larger flowers.

“For perennials that have leaves on the flower stem, I generally cut just above a leaf node. That way, the cut becomes hidden by the leaf,” she said, “For flowers
with a leafless stem, like daylilies, cut them down to the base of the plant and remove the entire stem.”

Many gardeners find the seed-head free look most attractive. But besides appearance and forcing re-bloom, there’s another reason to remove spent flowers. It’s actually the same reason some gardeners leave on seed heads. When some plants are allowed to set seed, you get baby plants.

There are perennials that are famously great self-seeders. Columbine, for one, loves to roam and spread its pretty seedlings to places garden far away from the parent plant. Globe Thistle is another one that likes big families.

Having baby plants about can help you fill in areas of your garden or allow you to share plants with other gardeners. Brister feels each gardener should decide for themselves whether to deadhead or not to deadhead.

“Echinacea seeds a lot. I get a carpet of seedlings every year. It’s not a "thug" because it is easy to remove, but still the seedlings need to be relocated or removed much of the time,” she said, “Butterfly Weed can do the same thing, but with both these plants, I love to leave the seeds on the plant, so it's a personal decision.”

If you want to encourage your plants to self-seed, you won’t be able to use any pre-emergent herbicides in your garden. They block germination of all seeds; both weed seeds and perennial flower seeds.

There are particularly attractive seed heads.

“Some plants have very decorative seed pods, Pasque Flower for instance,” she said, “And plants like Liatris are great for attracting gold finches with their seeds.”

If cutting your plants back and seed heads aren’t for you, there are plants that don’t need to be spruced up after blooming.

“Some perennials like Columbine and Baptisia are self cleaning,” said Brister, “Another low maintenance way to go would be to plant fall bloomers - when they are done blooming just cut them to the ground and you've done your fall clean up.”
Every garden is different and they should be. If you love birds perching on your Echinacea and snacking, leave on the seed heads. Neat can be over-rated.