AT A GLANCE
Family: Nightshade Height: 6 to 24 inches A/B/P, Hardiness: half-hardy annual Spacing: 2 per square
Growing Season Spring: late Summer: yes Fall: early Winter: no
Seed to Harvest/Flower: 14 weeks Seeds Storage:
Weeks to Maturity: 8 to 10 weeks Indoor Seed Starting: 8 to 10 weeks before first frost Earliest Outdoor Planting: after last frost
Additional Plantings: not needed Last Planting: not needed
Petunias are one of the easiest annuals to grow, especially if they are purchased as plants. They are branching, creeping plants with light-green, hairy leaves that can be sticky. The trumpet-shaped flowers come in just about every color imaginable, even the once-impossible yellow, and the flower forms range from single to double, ruffled, striped, and scalloped. Petunia flowers come in a range of sizes— grandifloras have 4 to 5 inch flowers, multifloras have 2 to 3 inch flowers, and millifloras have an abundance of tiny 1-inch flowers. Pinch petunia plants back by about one-third before planting, then keep them deadheaded and pruned throughout the growing season for a non-stop performance.
Location: full sun to partial shade
Seeds Indoors: Start seeds indoors 8-10 weeks before last frost, 12 to 14 weeks for slower growing varieties. Don't cover the seeds. Petunias can germinate slowly, from 7 to 21 days. Transplanting: Set petunias out when all danger of frost has passed. Pinch at transplanting for better branching.
Basil and Beyond
Watering: Weekly, 1 cup per plant.
Maintenance: Deadhead to encourage bloom, and prune back by half if the plant gets scraggly.
Aphids; gray mold and soft rot can occur in humid areas.
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