Kailua, HI Frost Dates
Published: February 1, 2026 · Updated: April 23, 2026
USDA Zone 12a
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
Kailua is essentially frost-free. Year-round gardening is possible.
Kailua’s zone 12a climate means frost is a minor consideration. Tropical year-round. No frost history. Hawaii and similar tropical locations. Rather than a single planting season, Kailua gardeners work almost year-round.
Complete Planting Calendar for Kailua
Lawn Care Timing for Kailua
Based on Kailua's USDA zone 12a frost dates: The last frost of Frost-free marks when warm-season grasses begin recovering. Apply spring fertilizer in Year-round (light monthly applications) when soil reaches 55°F. The first fall frost of Frost-free sets your deadlines — complete overseeding by Not applicable and apply winterizer by Not applicable.
USDA Zone 12a Summary
Tropical year-round. No frost history. Hawaii and similar tropical locations.
Frequently Asked Questions
What is the last frost date in Kailua, HI?
The average last spring frost in Kailua is Frost-free. This is based on USDA zone 12a 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 Kailua?
Kailua’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 Kailua?
Kailua 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 Kailua?
The prime overseeding window in Kailua is Not applicable. This ensures warm soil for germination before the first fall frost on Frost-free.
When should I apply winterizer in Kailua?
Apply winterizer fertilizer in Kailua 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.