🎆 Dahlia

Dahlia pinnata
The diva of the cutting garden — high maintenance, worth every minute.
Sun
Full sun, 6+ hrs
Days to harvest
Tubers sprout in 2–3 weeks; blooms summer–fall
Spacing
12–18 inches apart
Soil pH
6.5–7.0

How to grow

Plant tubers 4–6 inches deep in spring after frost — in Florida zones 9–11 they can stay in the ground year-round with mulch; north of zone 8, dig and store for winter. Stake tall varieties at planting time (not after — you'll spear the tuber). Pinch the growing tip at 12 inches for bushier plants and more blooms.

Water & feeding

Water deeply once growing; keep soil evenly moist but not soggy. Mulch to keep tubers cool.

Common problems

  • Slugs and earwigs chewing buds and petals
  • Powdery mildew in humid, crowded plantings
  • Tuber rot in cold, wet soil

Harvest

Cut early and often — dahlias are the ultimate cut-and-come-again flower, and cutting IS deadheading. Harvest in the cool morning when blooms are 3/4 open.

Nerdy fact: Dahlias were first grown as a food crop — the Aztecs ate the tubers, which taste faintly like a cross between potato and radish. Europe decided the flowers were prettier than the dinner and never looked back.

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