Whether you’re cultivating dahlias in pots or have a sizeable patch in your outdoor space, their stunning, eye-catching flowers are guaranteed to enchant. To maximize your dahlia yield and extend their blooming period, there’s a simple yet key technique to master: deadheading. Use these guidelines on the proper timing and method of deadheading to keep your dahlias’ floral splendor going all summer.
As with many flowering plants, dahlias produce blooms as part of their reproductive process. When the flowers wither and the petals drop, the plant naturally shifts its energy towards seed production. Snipping off the flower before seeds form diverts this energy back into creating more flowers.
Unless you’re harvesting and saving seeds for the following year (which isn’t advisable for hybrids as they may not grow true to type), there’s no benefit to letting your dahlias go to seed. The plant will still generate tubers that can be lifted and divided, providing identical daughter plants for the next growing season.
Deadheading also helps maintain a tidier appearance in your dahlias. Wilting flowers often turn brown, droop, and become untidy before shedding their petals.
The best time to start deadheading depends on the variety and growth stage of your dahlias. They don’t all bloom at the same pace after planting; some may start flowering within 75 days, while others may take over three months. Bedding dahlias, especially if purchased in bloom from a garden center, will need immediate attention.
Remove blooms as they begin to fade and lose their appeal. There’s no need to wait until they turn brown or the petals drop. A weekly deadheading session is typically sufficient to encourage your dahlia to keep blooming throughout the season.
Once you begin deadheading, continue the practice until the first frost takes care of the aboveground parts of the plant.
The process of deadheading dahlias is straightforward and requires sharp gardening shears or scissors. Choose a spent flower and trim the stem at least 12 inches below the bloom to promote the growth of longer stems. For bedding or dwarf dahlias, cut just below a leaf node, as you would with other potted plants, to keep it inconspicuous. Sanitize your pruning tools between plants to prevent the spread of diseases that are common in dahlias. A bleach solution (one part bleach to nine parts water) or rubbing alcohol can be used for this purpose. Dispose of the deadheaded flowers in your compost bin, or in the yard waste bin if they came from a diseased plant.
FAQs
Yes, pinching dahlias involves snipping the tip of the main stem when it reaches 10-12 inches, which encourages the growth of additional branches. This is particularly beneficial for larger dahlia varieties, preventing the flower stalks from becoming too long for bouquets.
If your dahlias aren’t flowering yet, it could simply be that they’re not ready. Early varieties like ‘Amber Queen’ may bloom within 75 days, while later ones like ‘Cafe Au Lait’ may take 120 days. If your dahlias are healthy and receiving sunlight, a bit of patience may be all that’s needed.
