Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Northbrook, IL, based on the USDA Hardiness Zone 6a.
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Northbrook, IL Frost Dates & Growing Season
Last Spring Frost Date for Northbrook, IL
The average last frost date in spring for Northbrook is April 30th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until May 14th 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 Northbrook, IL
The average first frost date in fall for Northbrook is October 25th. 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 Northbrook, IL
Based on historical frost data, the estimated growing season length in Northbrook is approximately 178 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.
Northbrook, IL Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Northbrook, IL Monthly Planting Recommendations
February
In February, recommended activities include starting Leek seeds indoors (from February 19th to March 5th), starting Impatiens seeds indoors (from February 19th to March 5th), and starting Lavender seeds indoors (from February 19th to March 5th).
March
In March, recommended activities include starting Coleus seeds indoors (from March 5th to March 19th), starting Basil seeds indoors (from March 19th to April 2nd), and starting Tomato seeds indoors (from March 5th to March 19th).
April
In April, recommended activities include direct sowing Potato (from April 2nd to April 16th), direct sowing Crimson Clover (from April 2nd to April 16th), and direct sowing Dill (from April 16th to April 30th).
May
In May, recommended activities include direct sowing Cosmos (from May 7th to May 14th), direct sowing Sesame (from May 14th to May 28th), and direct sowing Sunflower (from May 7th to May 21st).