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Belfast Frost Dates & Growing Season
Here's the frost forecast for the next three days (last updated on December 8th, 2025 6:07 AM).
Dec 8th
Safe
Dec 9th
Safe
Dec 10th
Safe
Last Frost Date (Spring)
The average last frost date for Belfast is April 20th. We recommend waiting until May 4th before planting tender crops outdoors.
First Frost Date (Autumn)
The average first frost date for Belfast is November 20th.
Growing Season
Based on historical data, the growing season in Belfast is approximately 214 days long.
Belfast Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting.
Belfast Monthly Gardening Guide
February
In February, you can start Artichoke indoors, start Begonia indoors, start Rue indoors, start Pansy indoors, and start Petunia indoors.
March
In March, you can start Brussel Sprout indoors, sow Alfalfa outside, start Marigold indoors, sow California Poppy outside, and sow Pea outside.
April
In April, you can sow Cosmos outside, sow Lemon Balm outside, sow Pumpkin outside, sow Moss Rose outside, and sow Gladiolus outside.
May
In May, you can sow Watermelon outside, sow Butterfly Pea outside, sow Okra outside, sow Melon outside, and sow Lima Bean outside.