Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Fort collins, CO, based on the USDA Hardiness Zone 5b.
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Fort collins, CO Frost Dates & Growing Season
Last Spring Frost Date for Fort collins, CO
The average last frost date in spring for Fort collins is May 6th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until May 20th 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 Fort collins, CO
The average first frost date in fall for Fort collins is October 4th. 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 Fort collins, CO
Based on historical frost data, the estimated growing season length in Fort collins is approximately 151 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.
Fort collins, CO Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Fort collins, CO Monthly Planting Recommendations
February
In February, recommended activities include starting Snapdragon seeds indoors (from February 25th to March 11th), starting Celery seeds indoors (from February 25th to March 11th), and starting Onion seeds indoors (from February 25th to March 11th).
March
In March, recommended activities include starting Sage seeds indoors (from March 25th to April 8th), starting Cabbage seeds indoors (from March 11th to March 25th), and starting Moonflower seeds indoors (from March 25th to April 8th).
April
In April, recommended activities include direct sowing Sorrel (from April 8th to April 22nd), starting Pumpkin seeds indoors (from April 15th to April 22nd), and direct sowing Potato (from April 8th to April 22nd).
May
In May, recommended activities include direct sowing Moss Rose (from May 13th to May 27th), direct sowing Cosmos (from May 13th to May 20th), and direct sowing Butternut Squash (from May 13th to May 27th).