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Merthyr Tydfil Frost Dates & Growing Season
Here's the frost forecast for the next three days (last updated on December 8th, 2025 6:08 AM).
Dec 8th
Safe
Dec 9th
Safe
Dec 10th
Safe
Last Frost Date (Spring)
The average last frost date for Merthyr Tydfil is May 5th. We recommend waiting until May 19th before planting tender crops outdoors.
First Frost Date (Autumn)
The average first frost date for Merthyr Tydfil is November 1st.
Growing Season
Based on historical data, the growing season in Merthyr Tydfil is approximately 180 days long.
Merthyr Tydfil Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting.
Merthyr Tydfil Monthly Gardening Guide
February
In February, you can start French Lavender indoors, start Snapdragon indoors, start Lavender indoors, start Celery indoors, and start Impatiens indoors.
March
In March, you can start Moonflower indoors, start Kale indoors, start Luffa indoors, start Rue indoors, and start Pepper indoors.
April
In April, you can sow Milk Thistle outside, start Cantaloupe indoors, sow German Chamomile outside, sow Flax outside, and sow Radish outside.
May
In May, you can sow Zinnia outside, sow Fenugreek outside, sow Lima Bean outside, sow Cucumber outside, and sow Watermelon outside.