Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Postville, IA, based on the USDA Hardiness Zone 4b.
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Postville, IA Frost Dates & Growing Season
Last Spring Frost Date for Postville, IA
The average last frost date in spring for Postville is May 10th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until May 24th 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 Postville, IA
The average first frost date in fall for Postville is October 5th. 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 Postville, IA
Based on historical frost data, the estimated growing season length in Postville is approximately 148 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.
Postville, IA Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Postville, IA Monthly Planting Recommendations
March
In March, recommended activities include starting Black Eyed Susan seeds indoors (from March 15th to March 29th), starting Impatiens seeds indoors (from March 1st to March 15th), and starting Basil seeds indoors (from March 29th to April 12th).
April
In April, recommended activities include direct sowing Sweet Pea (from April 12th to April 26th), direct sowing Alfalfa (from April 12th to April 26th), and direct sowing Cilantro (from April 26th to May 24th).
May
In May, recommended activities include direct sowing Gladiolus (from May 10th to May 24th), direct sowing Cosmos (from May 17th to May 24th), and direct sowing Fenugreek (from May 10th to May 24th).