Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Roy, MT, based on the USDA Hardiness Zone 4a.
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Roy, MT Frost Dates & Growing Season
Last Spring Frost Date for Roy, MT
The average last frost date in spring for Roy 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 Roy, MT
The average first frost date in fall for Roy 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 Roy, MT
Based on historical frost data, the estimated growing season length in Roy 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.
Roy, MT Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Roy, MT Monthly Planting Recommendations
March
In March, recommended activities include starting Pansy seeds indoors (from March 16th to March 30th), starting Broccoli seeds indoors (from March 30th to April 13th), and starting Geranium seeds indoors (from March 16th to March 30th).
April
In April, recommended activities include starting Sage seeds indoors (from April 13th to April 27th), direct sowing Spinach (from April 13th to April 27th), and direct sowing Sorrel (from April 27th to May 11th).
May
In May, recommended activities include direct sowing Alyssum (from May 11th to May 25th), direct sowing Lentil (from May 11th to May 25th), and direct sowing Cilantro (from May 11th to June 8th).
June
In June, recommended activities include direct sowing Pumpkin (from June 1st to June 15th), direct sowing Jute (from June 8th to June 22nd), and direct sowing Butterfly Pea (from June 8th to June 22nd).