San Diego, CA Frost Dates
Published: February 1, 2026 · Updated: April 23, 2026
USDA Zone 10b
Last Spring Frost
Frost-free
Safe to transplant after this date
First Fall Frost
Frost-free
Protect tender plants before this date
Frost-Free Season
365 days
Year-round to Year-round
San Diego is essentially frost-free. Year-round gardening is possible.
San Diego’s zone 10b climate means frost is a minor consideration. Completely frost-free. Tropical conditions year-round. South Florida, Hawaii. Rather than a single planting season, San Diego gardeners work almost year-round.
Complete Planting Calendar for San Diego
Lawn Care Timing for San Diego
Based on San Diego's USDA zone 10b frost dates: The last frost of Frost-free marks when warm-season grasses begin recovering. Apply spring fertilizer in February–March when soil reaches 55°F. The first fall frost of Frost-free sets your deadlines — complete overseeding by October–November and apply winterizer by Not applicable.
USDA Zone 10b Summary
Completely frost-free. Tropical conditions year-round. South Florida, Hawaii.
Frequently Asked Questions
What is the last frost date in San Diego, CA?
The average last spring frost in San Diego is Frost-free. This is based on USDA zone 10b historical averages. Plan transplanting and spring lawn care around this date — wait 2 weeks after for frost-sensitive plantings.
When is the first fall frost in San Diego?
San Diego’s average first fall frost is Frost-free. This sets deadlines for fall overseeding (must be done when temperatures cool) and winterizer application (by Not applicable).
When should I plant tomatoes in San Diego?
San Diego is frost-free — transplant tomato seedlings outdoors year-round. Direct sow warm-season crops year-round (no frost risk).
When should I overseed my lawn in San Diego?
The prime overseeding window in San Diego is October–November. This ensures warm soil for germination before the first fall frost on Frost-free.
When should I apply winterizer in San Diego?
Apply winterizer fertilizer in San Diego by Not applicable. This high-potassium application hardens grass cell walls before freeze damage. Your first fall frost of Frost-free is the hard deadline.