Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Cortland, IL, based on the USDA Hardiness Zone 5b.
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Cortland, IL Frost Dates & Growing Season
Last Spring Frost Date for Cortland, IL
The average last frost date in spring for Cortland is May 1st. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until May 15th 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 Cortland, IL
The average first frost date in fall for Cortland is October 10th. 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 Cortland, IL
Based on historical frost data, the estimated growing season length in Cortland is approximately 162 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.
Cortland, IL Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Cortland, IL Monthly Planting Recommendations
February
In February, recommended activities include starting Impatiens seeds indoors (from February 20th to March 6th), starting Begonia seeds indoors (from February 20th to March 6th), and starting Geranium seeds indoors (from February 20th to March 6th).
March
In March, recommended activities include starting Moonflower seeds indoors (from March 20th to April 3rd), starting Stevia seeds indoors (from March 6th to March 20th), and direct sowing Pea (from March 20th to April 3rd).
April
In April, recommended activities include direct sowing Chives (from April 3rd to April 17th), direct sowing Alyssum (from April 17th to May 1st), and direct sowing Flax (from April 3rd to April 17th).
May
In May, recommended activities include direct sowing Pumpkin (from May 8th to May 22nd), direct sowing Fenugreek (from May 1st to May 15th), and direct sowing Cosmos (from May 8th to May 15th).