Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Manhattan, MT, based on the USDA Hardiness Zone 4b.
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Manhattan, MT Frost Dates & Growing Season
Last Spring Frost Date for Manhattan, MT
The average last frost date in spring for Manhattan is June 5th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until June 19th 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 Manhattan, MT
The average first frost date in fall for Manhattan is September 15th. 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 Manhattan, MT
Based on historical frost data, the estimated growing season length in Manhattan 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.
Manhattan, MT Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Manhattan, MT Monthly Planting Recommendations
March
In March, recommended activities include starting Snapdragon seeds indoors (from March 27th to April 10th), starting Begonia seeds indoors (from March 27th to April 10th), and starting Petunia seeds indoors (from March 27th to April 10th).
April
In April, recommended activities include starting Aubergine seeds indoors (from April 10th to April 24th), starting Brussel Sprout seeds indoors (from April 24th to May 8th), and starting Ground Cherry seeds indoors (from April 10th to April 24th).
May
In May, recommended activities include direct sowing Cilantro (from May 22nd to June 19th), direct sowing Hyssop (from May 22nd to June 5th), and direct sowing Parsley (from May 8th to May 22nd).
June
In June, recommended activities include direct sowing Cantaloupe (from June 12th to June 26th), direct sowing Pumpkin (from June 12th to June 26th), and direct sowing Melon (from June 19th to July 3rd).