Deadheading is the process of removing spent flowers from plants. When you pinch or cut off fading flowers, the plant puts its energy back into making more flowers, prolonging their color in the garden. With some plants, you can also get a second bloom. Here are some favorite perennials and annuals that benefit from deadheading, and some tips on how to do it.
Astilbe (Astilbe spp., Zones 4-8). Leave seedheads standing until unattractive, then cut to ground; doesn’t rebloom.
Balloon flower (Platycodon grandiflorus, Zones 4-9). Remove individual spent flowers; sap is sticky, clean pruner with alcohol; can rebloom.
Bee balm (Monarda didyma, Zones 4-9). Cut back to side buds; when finished flowering, cut back to 4 or 5 inches to promote healthy foliage; doesn’t rebloom.
Cardinal flower (Lobelia cardinalis, Zones 3-9). Cut flower spikes to 3 inches for a small rebloom.
Coral bells (Heuchera spp., Zones 4-8). Cut stems below the foliage mound; will sometimes have a small rebloom.
Cosmos (Cosmos spp., annual). Cut individual flower stalks to first leaves to promote branching and reblooming.
Dahlia (Dahlia spp., annual in most climates). Cut individual flower stalks to first leaves to promote branching and reblooming.
Daylily (Hemerocallis spp., Zones 3-10). Snap off spent flowers to promote larger later flowers; cut finished stems to the ground; some cultivars rebloom, others don’t.
Dianthus (Dianthus gratianopolitanus, Zones 3-8). Deadhead as soon as flowers fade to prevent reseeding; remove stems but allow foliage clump to remain; doesn’t rebloom.
Foxglove (Digitalis purpurea, Zones 4-8). Pinch individual flowers along stem; when stem is finished, cut to the ground; may rebloom with smaller flowers.
Geranium (Pelargonium spp., annual). Pinch spent flower stalks below the foliage; will bloom continuously through fall.
Jacob’s ladder (Polemonium caeruleum, Zones 4-8). Cut entire plant to the ground to encourage fresh, new growth; often reblooms.
Lavender (Lavandula angustifoli, Zones 5-8). Cut flower stems back to healthy foliage; second blooms are shorter than the first; cut late flowers, leaving foliage.
Monkshood (Aconitum napellus, Zones 5-8). Cut off spent florets; cut to side branches to promote bloom; cut to ground to promote second bloom; wear gloves to keep hands safe from poisonous sap.
New England aster (Aster nova-angliae, Zones 4-8). Shear stems back to the foliage; cut back by half in early summer to control height and promote bushiness and reblooming.
Penstemon (Penstemon barbatus, Zones 4-9). Cut side branches to prolong bloom; cut stems to ground when finished; doesn’t rebloom.
Petunia (Petunia spp., annual). Pinch back to the first set of leaves to promote bushiness and reblooming.
Purple coneflower (Echinacea purpurea, Zones 3-9). Reblooms without deadheading; cut early blooms to side shoots to promote larger late flowers.
Siberian iris (Iris sibirica, Zones 4-9). Pinch spent flowers from stem; cut stem to ground when finished blooming; doesn’t rebloom.
Snapdragon (Antirrhinum spp., annual). Cut flower spikes back to foliage when they fade for a fall rebloom.
Tall garden phlox (Phlox paniculata, Zones 4-8). Shear off spent flower clusters; cut to ground when finished blooming; seeds will revert to less desirable colors; doesn’t rebloom.
Threadleaf coreposis (Coreopsis verticillata, Zones 4-9). Shear plants to ground in late summer for early fall rebloom.
Zinnia (Zinnia spp., annual). Cut individual flower stalks to first leaves to promote branching and reblooming.