Use this planting calendar to find the best times of the year to grow fruits, vegetables, herbs, flowers, and other popular plants in Harper, OR, based on the USDA Hardiness Zone 6a.
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Harper, OR Frost Dates & Growing Season
Last Spring Frost Date for Harper, OR
The average last frost date in spring for Harper is May 28th. For gardeners planting sensitive crops like tomatoes, peppers, and basil, it is generally recommended to wait until June 11th 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 Harper, OR
The average first frost date in fall for Harper is September 10th. 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 Harper, OR
Based on historical frost data, the estimated growing season length in Harper is approximately 105 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.
Harper, OR Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting your plants.
Harper, OR Monthly Planting Recommendations
March
In March, recommended activities include starting French Lavender seeds indoors (from March 19th to April 2nd), starting Petunia seeds indoors (from March 19th to April 2nd), and starting Geranium seeds indoors (from March 19th to April 2nd).
April
In April, recommended activities include direct sowing Sweet Pea (from April 30th to May 14th), starting Tomato seeds indoors (from April 2nd to April 16th), and starting Cabbage seeds indoors (from April 2nd to April 16th).
May
In May, recommended activities include direct sowing Lemon Balm (from May 28th to June 11th), direct sowing Hyssop (from May 14th to May 28th), and direct sowing Fenugreek (from May 28th to June 11th).
June
In June, recommended activities include direct sowing Zinnia (from June 4th to June 18th), direct sowing Cucumber (from June 4th to June 18th), and direct sowing Cosmos (from June 4th to June 11th).