Seneca, OR frost dates

Gardening where frost is possible all year

The weather station nearest Seneca, OR records freezing temperatures in every month often enough that NOAA cannot define a frost-free season. Gardening is still possible — it just means planning for frost at any time:

• Grow fast, cold-tolerant crops: Radishes, Lettuce, Spinach, Kale, Peas, Potatoes, Swiss Chard, Garlic.
• Plant once the soil can be worked — usually late spring to early summer at high elevation — and keep row covers ready for clear, still nights.
• Use season extension: cold frames, low tunnels, wall-of-water cloches or a greenhouse turn a few frost-free weeks into a real season.
• Frost-tender crops (tomatoes, squash, beans) need protection all season; choose the earliest varieties you can find.

About these dates

Based on 1991–2020 NOAA climate normals for the Seneca, OR weather station, about 1 km away (elevation 4,659 ft (1,420 m)).

Frost dates near Seneca

• Canyon City May 28 · Sep 18
• John Day May 28 · Sep 18
• Mount Vernon May 28 · Sep 18
• Prairie City frost any month
• Drewsey Jun 5 · Sep 5
• Dayville May 4 · Oct 6
• Hines Jun 11 · Sep 6
• Paulina frost any month
• Burns Jun 11 · Sep 6
• Bates frost any month

Frequently asked questions

When is the last frost in Seneca, OR?

Seneca, OR can freeze in any month, so there is no reliable last frost date. The nearest NOAA station averages 252 nights a year at or below 32°F.

What can I grow in Seneca, OR?

Fast, cold-tolerant crops such as radishes, lettuce, spinach, kale, peas and potatoes, ideally under row covers, cold frames or a greenhouse. Frost-tender crops like tomatoes need protection all season.