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Horsham Frost Dates & Growing Season
Here's the frost forecast for the next three days (last updated on December 8th, 2025 6:04 AM).
Dec 8th
Safe
Dec 9th
Safe
Dec 10th
Safe
Last Frost Date (Spring)
The average last frost date for Horsham is April 25th. We recommend waiting until May 9th before planting tender crops outdoors.
First Frost Date (Autumn)
The average first frost date for Horsham is November 15th.
Growing Season
Based on historical data, the growing season in Horsham is approximately 204 days long.
Horsham Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting.
Horsham Monthly Gardening Guide
February
In February, you can start Pansy indoors, start Broccoli indoors, start French Lavender indoors, start Leek indoors, and start Snapdragon indoors.
March
In March, you can start Moonflower indoors, sow Chives outside, start Swamp Milkweed indoors, sow Arugula outside, and start Sage indoors.
April
In April, you can sow Carrot outside, sow Lemon Balm outside, sow Milk Thistle outside, sow Quinoa outside, and sow Dill outside.
May
In May, you can sow Zucchini outside, sow Morning Glory outside, sow Melon outside, sow Cucumber outside, and sow Cosmos outside.