Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Jefferson city, MT, based on the USDA Hardiness Zone 4b.
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Jefferson city, MT Frost Dates & Growing Season
Last Spring Frost Date for Jefferson city, MT
The average last frost date in spring for Jefferson city is June 10th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until June 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 Jefferson city, MT
The average first frost date in fall for Jefferson city 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 Jefferson city, MT
Based on historical frost data, the estimated growing season length in Jefferson city is approximately 102 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.
Jefferson city, MT Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Jefferson city, MT Monthly Planting Recommendations
April
In April, recommended activities include starting Marigold seeds indoors (from April 29th to May 13th), starting Thyme seeds indoors (from April 15th to April 29th), and starting Ground Cherry seeds indoors (from April 15th to April 29th).
May
In May, recommended activities include starting Cantaloupe seeds indoors (from May 13th to May 27th), direct sowing Kale (from May 13th to May 27th), and direct sowing Parsley (from May 13th to May 27th).
June
In June, recommended activities include direct sowing Butterfly Pea (from June 24th to July 8th), direct sowing Mung Bean (from June 24th to July 8th), and direct sowing Cosmos (from June 17th to June 24th).