On this page:
Cornwall Frost Dates & Growing Season
Here's the frost forecast for the next three days (last updated on January 13th, 2026 12:11 AM). You can also use the My Cozy Plant app for faster frost warnings and alerts in your postal code.
Jan 13th
False Security / Chilling Injury (Too cold for Basil)
Jan 14th
Radiation Frost (Clear skies froze leaves)
Jan 15th
Safe
Last Frost Date (Spring)
The average last frost date for Cornwall is March 30th. We recommend waiting until April 13th before planting tender crops outdoors.
First Frost Date (Autumn)
The average first frost date for Cornwall is December 5th.
Growing Season
Based on historical data, the growing season in Cornwall is approximately 250 days long.
Cornwall Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting.
Cornwall Monthly Gardening Guide
January
In January, you can start Pansy indoors, start Leek indoors, start Petunia indoors, start Snapdragon indoors, and start Lavender indoors.
February
In February, you can start Broccoli indoors, sow Spinach outside, start Stevia indoors, start Rue indoors, and sow Pea outside.
March
In March, you can sow California Poppy outside, sow Watercress outside, sow Fennel outside, sow Forget Me Not outside, and sow Sorrel outside.
April
In April, you can sow Lima Bean outside, sow Cosmos outside, sow Watermelon outside, sow Zinnia outside, and sow Morning Glory outside.