Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Casper, WY, based on the USDA Hardiness Zone 5a.
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Casper, WY Frost Dates & Growing Season
Last Spring Frost Date for Casper, WY
The average last frost date in spring for Casper is May 21st. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until June 4th 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 Casper, WY
The average first frost date in fall for Casper 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 Casper, WY
Based on historical frost data, the estimated growing season length in Casper is approximately 122 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.
Casper, WY Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Casper, WY Monthly Planting Recommendations
March
In March, recommended activities include starting Aubergine seeds indoors (from March 26th to April 9th), starting Geranium seeds indoors (from March 12th to March 26th), and starting Coleus seeds indoors (from March 26th to April 9th).
April
In April, recommended activities include direct sowing Radish (from April 23rd to May 7th), direct sowing California Poppy (from April 23rd to May 7th), and direct sowing Sweet Pea (from April 23rd to May 7th).
May
In May, recommended activities include direct sowing Pumpkin (from May 28th to June 11th), direct sowing Nasturtium (from May 28th to June 4th), and direct sowing Zucchini (from May 28th to June 11th).
June
In June, recommended activities include direct sowing Mung Bean (from June 4th to June 18th), direct sowing Watermelon (from June 4th to June 18th), and direct sowing Jute (from June 4th to June 18th).