Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Castle pines, CO, based on the USDA Hardiness Zone 5b.
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Castle pines, CO Frost Dates & Growing Season
Last Spring Frost Date for Castle pines, CO
The average last frost date in spring for Castle pines is May 19th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until June 2nd 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 Castle pines, CO
The average first frost date in fall for Castle pines is October 5th. 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 Castle pines, CO
Based on historical frost data, the estimated growing season length in Castle pines is approximately 139 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.
Castle pines, CO Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Castle pines, CO Monthly Planting Recommendations
March
In March, recommended activities include starting Celery seeds indoors (from March 10th to March 24th), starting Leek seeds indoors (from March 10th to March 24th), and starting Thyme seeds indoors (from March 24th to April 7th).
April
In April, recommended activities include direct sowing Mustard (from April 21st to May 5th), direct sowing Lettuce (from April 21st to May 5th), and direct sowing Alfalfa (from April 21st to May 5th).
May
In May, recommended activities include direct sowing Milk Thistle (from May 5th to May 19th), direct sowing Quinoa (from May 5th to May 19th), and direct sowing Fenugreek (from May 19th to June 2nd).
June
In June, recommended activities include direct sowing Watermelon (from June 2nd to June 16th), direct sowing Mung Bean (from June 2nd to June 16th), and direct sowing Sesame (from June 2nd to June 16th).