Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Sun river, MT, based on the USDA Hardiness Zone 4b.
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Sun river, MT Frost Dates & Growing Season
Last Spring Frost Date for Sun river, MT
The average last frost date in spring for Sun river is May 25th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until June 8th 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 Sun river, MT
The average first frost date in fall for Sun river is September 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 Sun river, MT
Based on historical frost data, the estimated growing season length in Sun river is approximately 123 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.
Sun river, MT Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Sun river, MT Monthly Planting Recommendations
March
In March, recommended activities include starting Cabbage seeds indoors (from March 30th to April 13th), starting Pepper seeds indoors (from March 30th to April 13th), and starting Thyme seeds indoors (from March 30th to April 13th).
April
In April, recommended activities include direct sowing Radish (from April 27th to May 11th), starting Brussel Sprout seeds indoors (from April 13th to April 27th), and direct sowing Lettuce (from April 27th to May 11th).
May
In May, recommended activities include direct sowing Calendula (from May 11th to May 25th), direct sowing Fennel (from May 11th to May 25th), and direct sowing Hyssop (from May 11th to May 25th).
June
In June, recommended activities include direct sowing Pumpkin (from June 1st to June 15th), direct sowing Melon (from June 8th to June 22nd), and direct sowing Butterfly Pea (from June 8th to June 22nd).