last frost

Asked April 3, 2019, 3:06 PM EDT

Hi there, and thank you in advance for any info you can share. I'm in Sweet Home, have checked the Farmer's Almanac, and the Weather Station outlook for an approximate last frost time, but i'm only finding conflicting info- as much as a month difference. Do you have a good estimate?

Benton County Oregon frost

1 Response

Thanks for your inquiry about when to expect the last spring freeze in Sweet Home. On average it appears to be mid-late April. Check out this map:

Data from the Hyslop weather station near Corvallis gives the average last frost date as April 25, based on over a century of data.

The reason there's a wide spread of possible times is that last frost date does vary by year. Some years it does not freeze in April and some years it has frozen in May.
But basically the chance of frost gets smaller the later it gets. So while it's not risk free to plant after mid-late April the chances your plants will freeze are low.

Page 7 of this publication has a helpful table with recommended times for direct seeding and indoor starts in your area: https://catalog.extension.oregonstate.edu/em9027