Dead flowers lingering on a lavender (Lavandula spp.) have one sole purpose: To manufacture and release the seeds that will grow into the next generation of plants. Removing -- or deadheading -- them before they complete the job keeps the seeds from sprouting where they aren't wanted, and lets the lavender divert energy from seed production to continued growth. In some cases, it may also result in a second round of blooms.
Cut the dead flowers before they're completely dry, or the seed capsules may burst and release the seeds.
Lavenders grow in U.S. Department of Agriculture plant hardiness zones 5 through 11, depending on variety, and they also bloom at different times of year. Planting more than one type may require several deadheading sessions.
How to Deadhead
Deadheading lavender flowers is no different from harvesting them for cooking or drying.
Things You'll Need
- Clean, sharp stem cutters
- Rubbing alcohol
- Clean rag or towel
- Trash bags
Cut each dead flower back to three to five leaf nodes before its base. Between cuts, wipe the stem cutters' blades with a clean rag dipped in rubbing alcohol to avoid spreading disease.
As you cut, drop the flowers into a trash bag for disposal so they don't shed seeds on the soil.
To speed the deadheading process on large lavender plants, grasp a bunch of spent flowers in one hand and cut them with the other. When you're finished, trim straggly ends back to leaf nodes to tidy the plant.