Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Oso, WA, based on the USDA Hardiness Zone 8a.
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Oso, WA Frost Dates & Growing Season
Last Spring Frost Date for Oso, WA
The average last frost date in spring for Oso 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 Oso, WA
The average first frost date in fall for Oso is October 1st. 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 Oso, WA
Based on historical frost data, the estimated growing season length in Oso is approximately 129 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.
Oso, WA Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Oso, WA Monthly Planting Recommendations
March
In March, recommended activities include starting Pepper seeds indoors (from March 30th to April 13th), starting Coneflower seeds indoors (from March 30th to April 13th), and starting Snapdragon seeds indoors (from March 16th to March 30th).
April
In April, recommended activities include direct sowing Crimson Clover (from April 27th to May 11th), direct sowing Chervil (from April 27th to May 11th), and starting Brussel Sprout seeds indoors (from April 13th to April 27th).
May
In May, recommended activities include direct sowing Fenugreek (from May 25th to June 8th), direct sowing Lemon Balm (from May 25th to June 8th), and direct sowing Quinoa (from May 11th to May 25th).
June
In June, recommended activities include direct sowing Corn (from June 8th to June 15th), direct sowing Cantaloupe (from June 1st to June 15th), and direct sowing Runner Bean (from June 1st to June 15th).