Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Idaho springs, CO, based on the USDA Hardiness Zone 5b.
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Idaho springs, CO Frost Dates & Growing Season
Last Spring Frost Date for Idaho springs, CO
The average last frost date in spring for Idaho springs is June 8th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until June 22nd 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 Idaho springs, CO
The average first frost date in fall for Idaho springs is September 15th. 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 Idaho springs, CO
Based on historical frost data, the estimated growing season length in Idaho springs is approximately 99 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.
Idaho springs, CO Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Idaho springs, CO Monthly Planting Recommendations
March
In March, recommended activities include starting Impatiens seeds indoors (from March 30th to April 13th), starting Pansy seeds indoors (from March 30th to April 13th), and starting Snapdragon seeds indoors (from March 30th to April 13th).
April
In April, recommended activities include starting Tomatillo seeds indoors (from April 13th to April 27th), starting Marigold seeds indoors (from April 27th to May 11th), and starting Tomato seeds indoors (from April 13th to April 27th).
May
In May, recommended activities include direct sowing Poppy (from May 11th to May 25th), direct sowing Mustard (from May 11th to May 25th), and direct sowing Beet (from May 25th to June 8th).
June
In June, recommended activities include direct sowing Nasturtium (from June 15th to June 22nd), direct sowing Mung Bean (from June 22nd to July 6th), and direct sowing Babys Breath (from June 8th to June 22nd).