Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Colo, CO, based on the USDA Hardiness Zone 6a.
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Colo, CO Frost Dates & Growing Season
Last Spring Frost Date for Colo, CO
The average last frost date in spring for Colo is May 5th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until May 19th before moving plants outdoors. Waiting these extra few weeks significantly reduces the risk of a late freeze damaging young transplants.
First Fall Frost Date for Colo, CO
The average first frost date in fall for Colo is September 25th. This date marks the approximate end of the growing season for tender plants. Gardeners should plan to harvest frost-sensitive vegetables or provide heavy protection (such as row covers) before this date to avoid crop loss.
Growing Season Length in Colo, CO
Based on historical frost data, the estimated growing season length in Colo is approximately 143 days. This duration determines which vegetable varieties have enough time to reach maturity before the winter cold sets in. Short-season varieties are recommended for crops that require a longer warm period.
Please note: These dates are climatological averages. Actual weather conditions vary by year. Always check the local 10-day forecast before planting.
Colo, CO Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Colo, CO Monthly Planting Recommendations
February
In February, recommended activities include starting Geranium seeds indoors (from February 24th to March 10th), starting Leek seeds indoors (from February 24th to March 10th), and starting Petunia seeds indoors (from February 24th to March 10th).
March
In March, recommended activities include starting Brussel Sprout seeds indoors (from March 24th to April 7th), starting Broccoli seeds indoors (from March 10th to March 24th), and starting Basil seeds indoors (from March 24th to April 7th).
April
In April, recommended activities include direct sowing Potato (from April 7th to April 21st), direct sowing Flax (from April 7th to April 21st), and direct sowing Kale (from April 7th to April 21st).
May
In May, recommended activities include direct sowing Black Bean (from May 19th to June 2nd), direct sowing Butternut Squash (from May 12th to May 26th), and direct sowing Moss Rose (from May 12th to May 26th).