🎺 Petunia

Petunia × hybrida
The trumpet section of the bedding-plant band.
Sun
Full sun, 6+ hrs
Days to harvest
Blooms 10–12 weeks from seed; transplants bloom sooner
Spacing
10–12 inches apart
Soil pH
6.0–7.0

How to grow

Start seeds indoors 10–12 weeks before the last frost — they need light to germinate, so don't cover them. In Florida, plant petunias in fall for winter-spring color; summer heat turns them leggy and sad. Wave types spread; grandifloras make the biggest trumpets.

Water & feeding

Water at the base when the top inch dries; soggy crowns invite rot, and overhead watering spots the flowers.

Common problems

  • Tobacco budworm caterpillars chew buds — handpick or use Bt
  • Gray mold in humid, crowded plantings; space and water at soil level
  • Leggy summer growth — shear back by a third to reboot

Harvest

Deadhead daily for non-wave types; waves are self-cleaning. Snip stems for bud vases.

Nerdy fact: Petunias are nightshade family — cousins of tomatoes and tobacco — and their trumpet flowers are pollinated by hawkmoths that hover like tiny hummingbirds after dark.

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