Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Seneca, OR, based on the USDA Hardiness Zone 5a.
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Seneca, OR Frost Dates & Growing Season
Last Spring Frost Date for Seneca, OR
The average last frost date in spring for Seneca is June 15th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until June 29th 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 Seneca, OR
The average first frost date in fall for Seneca is August 30th. 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 Seneca, OR
Based on historical frost data, the estimated growing season length in Seneca is approximately 76 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.
Seneca, OR Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Seneca, OR Monthly Planting Recommendations
April
In April, recommended activities include starting Tomato seeds indoors (from April 20th to May 4th), starting Coleus seeds indoors (from April 20th to May 4th), and starting Petunia seeds indoors (from April 6th to April 20th).
May
In May, recommended activities include direct sowing Bok Choy (from May 18th to June 1st), direct sowing Poppy (from May 18th to June 1st), and direct sowing Arugula (from May 18th to June 1st).
June
In June, recommended activities include direct sowing Cosmos (from June 22nd to June 29th), direct sowing Moss Rose (from June 22nd to July 6th), and direct sowing Babys Breath (from June 15th to June 29th).