Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Jamestown, CO, based on the USDA Hardiness Zone 5b.
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Jamestown, CO Frost Dates & Growing Season
Last Spring Frost Date for Jamestown, CO
The average last frost date in spring for Jamestown is June 6th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until June 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 Jamestown, CO
The average first frost date in fall for Jamestown is September 20th. 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 Jamestown, CO
Based on historical frost data, the estimated growing season length in Jamestown is approximately 106 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.
Jamestown, CO Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Jamestown, CO Monthly Planting Recommendations
March
In March, recommended activities include starting Petunia seeds indoors (from March 28th to April 11th), starting Impatiens seeds indoors (from March 28th to April 11th), and starting Geranium seeds indoors (from March 28th to April 11th).
April
In April, recommended activities include starting Ground Cherry seeds indoors (from April 11th to April 25th), starting Pepper seeds indoors (from April 11th to April 25th), and starting Aubergine seeds indoors (from April 11th to April 25th).
May
In May, recommended activities include direct sowing Fennel (from May 23rd to June 6th), direct sowing Bok Choy (from May 9th to May 23rd), and direct sowing Lentil (from May 23rd to June 6th).
June
In June, recommended activities include direct sowing Corn (from June 20th to June 27th), direct sowing Cantaloupe (from June 13th to June 27th), and direct sowing Lemon Balm (from June 6th to June 20th).