in , ,

When to Seed Start Annuals

Celosia in the garden
Celosia in the garden

Most annual flowers are frost-tender. Annual seeds should be sown outdoors after the last average frost date in spring. To get a head start on the season, seeds can be started indoors, and young plants can be set in the garden after the last frost.

Young plants of annuals started indoors should be hardened off before being transplanted into the garden. Harden off plants by exposing them to outdoor temperatures and sunlight for an hour or two each day for several days before transplanting.

Check the weather service or the cooperative extension near you for the average last frost date in spring where you live. Here’s when to start annual seeds indoors and when to set young transplants into the garden.

FlowerStart Seeds Indoors –weeks before the last frostTransplant into the garden
Ageratum6-8 weeksOn last frost date
Alyssum6-8 weeks1-2 weeks after last frost
Amaranth6-8 weeksAfter last frost
Bachelor’s Button6-8 weeksOn last frost date
Calendula6-8 weeks1-2 weeks after last frost
Celosia6-8 weeksOn last frost date
Coleus8-10 weeks1-2 weeks after last frost
Cosmos6-8 weeksOn last frost date
Delphinium6-8 weeks1-2 weeks after last frost
Gomphrena6-8 weeksOn last frost date
Marigold6-8 weeksOn last frost date
Morning Glory3-4 weeksAfter last frost
Nicotiana6-8 weeksOn last frost date
Pansy8-10 weeksOn last frost date
Petunia8-10 weeksOn last frost date
Pholox8-10 weeksOn last frost date
Portulaca6-8 weeksOn last frost date
Salvia6-8 weeksOn last frost date
Scabiosa6-8 weeksOn last frost date
Snapdragon8-10 weeksOn last frost date
Statice6-8 weeksOn last frost date
Stock8-10 weeksOn last frost date
Strawflower6-8 weeksOn last frost date
Sunflower3-4 weeks1-2 weeks after last frost
Verbena8-10 weeksOn last frost date
Zinnia4-6 week1-2 weeks after last frost

Also of interest:

24 Annuals to Plant in Summer

16 Drought Tolerant Annuals

Planting a Container

Swiss cheese plant

How to Grow and Care for Monstera — Swiss Cheese Plant

African violet

How to Grow and Care for African Violet–Saintpaulia