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What to Plant in December — USDA Zone 9b

Here's everything you can start, transplant, sow, and harvest in December in USDA Zone 9b. This zone has an average last spring frost around January 25 and first fall frost around December 20, with a growing season of approximately 329 days.

There are 33 planting activities for December in Zone 9b.

Zone 9b Year-round
329 days
Last Spring Frost January 25
329 growing days
First Fall Frost December 20

Where Is Zone 9b?

Transplant Outdoors in December

Plant Type Date Range Days to Maturity
Bachelor's Button Flower 60–90 days
Begonias Flower 70–90 days
Calendula Flower 50–70 days
Cosmos Flower 60–90 days
Dianthus Flower 60–80 days
Geraniums Flower 70–100 days
Lobelia Flower 70–80 days
Nasturtium Flower 55–65 days
Pansy Flower 70–90 days
Salvia Flower 70–90 days
Snapdragon Flower 70–100 days
Sunflower Flower 70–100 days
Sweet Alyssum Flower 45–60 days
Vinca (Annual) Flower 70–90 days
Zinnia Flower 60–70 days

Direct Sow in December

Plant Type Date Range Days to Maturity
Bachelor's Button Flower 60–90 days
Calendula Flower 50–70 days
Cosmos Flower 60–90 days
Dianthus Flower 60–80 days
Nasturtium Flower 55–65 days
Snapdragon Flower 70–100 days
Sunflower Flower 70–100 days
Sweet Alyssum Flower 45–60 days
Zinnia Flower 60–70 days

Harvest in December

Plant Type Date Range Days to Maturity
Alliums Flower 28–42 days
Anemones Flower 90–120 days
California Poppy Flower 60–90 days
Freesia Flower 84–112 days
Hyacinths Flower 14–28 days
Larkspur Flower 60–90 days
Ranunculus Flower 90–120 days
Strawberries Fruit 90–365 days
Sweet Pea Flower 65–85 days

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: July 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.