Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Hamilton, WA, based on the USDA Hardiness Zone 8b.
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Hamilton, WA Frost Dates & Growing Season
Last Spring Frost Date for Hamilton, WA
The average last frost date in spring for Hamilton 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 Hamilton, WA
The average first frost date in fall for Hamilton is October 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 Hamilton, WA
Based on historical frost data, the estimated growing season length in Hamilton is approximately 158 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.
Hamilton, WA Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Hamilton, WA Monthly Planting Recommendations
March
In March, recommended activities include starting Tomato seeds indoors (from March 15th to March 29th), direct sowing Spinach (from March 29th to April 12th), and starting Ground Cherry seeds indoors (from March 15th to March 29th).
April
In April, recommended activities include direct sowing Potato (from April 12th to April 26th), direct sowing Alfalfa (from April 12th to April 26th), and direct sowing Mustard (from April 12th to April 26th).
May
In May, recommended activities include direct sowing Chia (from May 24th to June 7th), direct sowing Mung Bean (from May 24th to June 7th), and direct sowing Runner Bean (from May 17th to May 31st).