Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Boulder hill, IL, based on the USDA Hardiness Zone 5b.
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Boulder hill, IL Frost Dates & Growing Season
Last Spring Frost Date for Boulder hill, IL
The average last frost date in spring for Boulder hill is April 28th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until May 12th 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 Boulder hill, IL
The average first frost date in fall for Boulder hill is October 13th. 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 Boulder hill, IL
Based on historical frost data, the estimated growing season length in Boulder hill is approximately 168 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.
Boulder hill, IL Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Boulder hill, IL Monthly Planting Recommendations
February
In February, recommended activities include starting Celery seeds indoors (from February 17th to March 3rd), starting Impatiens seeds indoors (from February 17th to March 3rd), and starting Lavender seeds indoors (from February 17th to March 3rd).
March
In March, recommended activities include direct sowing Sweet Pea (from March 31st to April 14th), starting Stevia seeds indoors (from March 3rd to March 17th), and starting Tomatillo seeds indoors (from March 3rd to March 17th).
April
In April, recommended activities include direct sowing Swiss Chard (from April 14th to April 28th), direct sowing Fenugreek (from April 28th to May 12th), and direct sowing Fennel (from April 14th to April 28th).
May
In May, recommended activities include direct sowing Cosmos (from May 5th to May 12th), direct sowing Black Bean (from May 12th to May 26th), and direct sowing Corn (from May 12th to May 19th).