If you’re new to gardening you may wonder why you see an experienced gardener pulling the spent blooms off their rose bush. Or snipping the flowers off a daffodil. They’re doing a simple kind of pruning called deadheading.
With deadheading, old growth and seed heads are “pinched” or cut off the plant to stimulate new growth and more flowers. As the only purpose (botanically speaking) of a flowering plant is to bloom and then set seed, deadheading tricks the plant into producing new blooms so it can set more seed. This extends the blooming season of the plant. It also keeps certain species from reseeding and keeps flowers and shrubs looking fresh and lively throughout the season.
After a plant is finished flowering, it begins to form seeds. The flowering process is suspended, and the plant begins to use all its energy to form seeds. Deadheading plants as soon as the blooms begin to fade will promote a second bloom…
When dead blooms are left clinging to flowering plants, they sap the nutrition and strength from the core of the plants and rob them of the energy to produce new and colorful blooms. The deadheading process redirects plants energy from seed production to root and vegetative growth.
To Deadhead or Not?, Penn State Extension
How to deadhead flowers
There’s nothing to be hesitant about, as deadheading is very simple and good for the plant. As flower blooms start to look scruffy, “pinch” them at the base where they meet the stem and gently pull the spent bloom from the plant. For thicker stems like roses, cut the flower stems in between the dying bloom and the closest set of healthy leaves. But take care that you don’t snip off new flower buds!
A note about deadheading roses: Some varieties of roses produce rose hips at the base of the flower, like those seen in the image above of pinching. The hip is the fruit of a rose and contains many small seeds. If left on the plant, the hips will swell and fill with natural sugars and a high level of vitamin C. They’re an important source of food for wildlife in the fall, are very colorful, and are also used in foods like teas and jams. So if your rose produces hips, you may wish not to deadhead your plant or deadhead just a portion of it as I do.
When to deadhead flowers
A flower bloom can last from one day to several weeks and weather conditions like heat, wind, and rain affect blooming a great deal. A simple walk around your garden once a day will show you which plants need deadheading and which don’t.
Deadhead a flower as soon as the bloom starts to decline and looks like it’s seen better days. How often depends on the plant, but a little observation will help you figure it out.
- A daylily bloom fades after – you guessed it – one day. The daylily deadheads itself and the dying bloom will fall off after a few days. But deadheading makes the plant look nicer.
- A peony bloom lasts for roughly one week, but when on the decline, scatters its petals in a thick mass below the plant (this might be good or bad depending on your point of view). Additionally, deadheading can encourage some varieties to produce side buds after the main bud blooms.
- Deadheading can stimulate new blooms on many flowering plants such as marigolds, zinnias, hollyhocks, and butterfly bush. (see chart below)
Not all flowering plants should be deadheaded
Don’t deadhead everything you see. Some flowering plants like Hollyhock, Columbine, and Foxglove can be left to go to seed so that you’ll see them again next year. Columbines may produce new plants from seed in the same season. So you may wish to let these plants go their natural course. Reserve your deadheading for daylilies, roses, astilbe, coreopsis, Monarda (bee balm), and others.
Consider stopping deadheading in the fall. As food supplies dwindle for birds and other wildlife, flower seed heads become an important source of nutrition. Leave most flower heads intact at the end of the season, as you’re past the time that plants can produce new blooms. Plus, some seed heads are beautiful in the fall as they die back and turn to yellow, red, or brown against a winter landscape.
Here’s a great video from Fraser Valley Rose Farm on techniques for deadheading many annuals and perennials.
Flowers That Benefit From Deadheading
Annuals and perennials that may produce additional blooms after removing spent flowers. Deadheading perennials can improve their appearance but may not produce new blooms. This is not a complete list.| Scientific name | Common Name | |
|---|---|---|
| Dianthus | Allwood pinks, Cheddar pinks | Will encourage new blooms |
| Gypsophila paniculata | Baby’s breath | Will encourage new blooms and tidy up the plant |
| Monarda | Bee Balm | Will encourage new blooms |
| Begonia grandis ssp. | Begonia | Flowers fall off naturally but deadheading tidies up the plant |
| Campanula | Bellflower | Will encourage new blooms |
| Gaillardia | Blanket Flower | Will encourage new blooms |
| Buddleja | Butterfly Bush | Will encourage new blooms |
| Asclepias tuberosa | Butterfly Weed | Encourages new blooms and controls seeding |
| Camellia japonica | Camellia | To tidy up the plant – will not rebloom |
| Aquilegia | Columbine | To control seeding. |
| Heucheras | Coral bells | Will encourage new blooms |
| Cosmos bipinnatus | Cosmos | Will encourage new blooms |
| Geranium | Cranesbill | Will encourage new blooms |
| Veronicastrum virginicum | Culver’s root | For rebloom and to control seeding |
| Narcissus | Daffodil | Will not rebloom, but will keep the plant tidy. |
| Dahlia spp | Dahlia | Will encourage new blooms |
| Hesperis matronalis | Dame’s rocket | Will encourage new blooms |
| Hemerocallis spp. | Daylily | Will not encourage new blooms but will tidy up the plant |
| Delphinium elatum | Delphinium | Will encourage new blooms |
| Oenothera | Evening Primrose | To control seeding |
| Heliopsis helianthoides | False sunflower | Will encourage blooms and prevent self-seeding |
| Phlox paniculata | Garden Phlox | For rebloom and to control seeding |
| Geum | Geum spp. | Will encourage new blooms |
| Echinops ritro | Globe thistle | To control seeding. |
| Anthemis tinctoria | Golden marguerites | Will encourage new blooms |
| Gaura lindheimeri | Guara | For rebloom and to control seeding |
| Geranium | Hardy geranium, storkbill, cranesbill | Will encourage new blooms |
| Alcea rosea | Hollyhocks | Will encourage new blooms |
| Hydrangeas | Hydrangea spp. | Will not encourage more blooms. |
| Anchusa azurea | Italian bugloss | Encourages new blooms and controls seeding |
| Centranthus | Jupiter’s Beard | To control seeding. |
| Alchemilla mollis | Lady’s Mantle | To control seeding |
| Lantana | Lantana | Will encourage new blooms |
| Delphinium | Larkspur | Will encourage new blooms |
| Lavatera | Lavatera spp. | Will encourage new blooms |
| Lavandula | Lavender | To encourage new blooms and keep the plant tidy |
| Syringa | Lilac | To tidy up the plant-will not rebloom |
| Lilium | Lily | To tidy up the plant-will not rebloom |
| Agapanthus | Lily of the Nile | Encourages new blooms and controls seeding |
| Lupinus | Lupine | To encourage new blooms and keep the plant tidy |
| Tagetes | Marigolds | Will encourage new blooms |
| Astrantia major | Masterwort | Will encourage new blooms |
| Phlox | Phlox | Will encourage new blooms |
| Choisya ternata | Mexican orange blossom | To tidy up the plant – will not rebloom |
| Centaurea montana | Mountain bluet | Encourages new blooms and controls seeding |
| Veronica speciosa | New Zealand Hebe | Will encourage new blooms |
| Tanacetum coccineum | Painted daisy | Will encourage new blooms |
| Viola tricolor var. hortensis | Pansy | Will encourage new blooms |
| Penstemon barbatus | Penstemon | Will encourage new blooms |
| Paeonia spp. | Peony | To tidy up the plant – will not rebloom |
| Petunia spp. | Petunia | Will encourage new blooms |
| Pieris japonica | Pieris | To tidy up the plant-will not rebloom |
| Scabiosa | Pincushion | Encourages new blooms and controls seeding |
| Primula x polyantha | Polyanthus | Encourages new blooms and controls seeding |
| Echinacea purpurea | Purple coneflower | To control seeding. |
| Rhododendron spp | Rhododendron | To tidy up the plant – will not rebloom |
| Rosa rubiginosa | Rose | To tidy up the plant and encourage reblooming. |
| Lychnis coronaria | Rose campion | Encourages new blooms |
| Salvia nemorosa | Salvia | Will encourage new blooms |
| Eryngium | Sea holly | Will encourage new blooms |
| Leucanthemum x superbum | Shasta Daisy | Will encourage new blooms |
| Antirrhinum majus | Snapdragon | Will encourage new blooms |
| Helenium autumnale | Sneezeweed | Will encourage new blooms |
| Veronica spp | Speedwells | Will encourage new blooms |
| Tradescantia | Spiderwort | Will encourage new blooms |
| Stokesia laevis | Stokes’ aster | Will encourage new blooms |
| Lobularia maritima | Sweet alyssum | Will encourage new blooms |
| Lathyrus odoratus | Sweet pea | Will encourage new blooms |
| Coreopsis | Tickseed | For rebloom and appearance |
| Paeonia suffruticosa | Tree peony | To tidy up the plant and control seeding-will not rebloom |
| Valeriana officinalis | Valerian | To control seeding |
| Achillea | Yarrow | For rebloom and to control seeding |
| Corydalis lutea | Yellow corydalis | Encourages new blooms and controls seeding |
| Zinnia elegans | Zinnia | Will encourage new blooms |
Sources: To Deadhead or not your final answer is, Penn State Extension; Plant Talk, Colorado State University; Deadheading Herbaceous Ornamentals and Roses, Iowa State University Extension.
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