Ogden, Utah: planting zone & frost dates
Ogden is in USDA plant hardiness zone 7a, where the average coldest winter night reaches 0 to 5°F (-17.8 to -15.0°C). The typical last spring frost is around Apr 28 and the first fall frost around Oct 17.
Frost dates
| Probability | Last spring frost (32°F) | First fall frost (32°F) |
|---|---|---|
| Safer (10% risk) | May 6 | Oct 8 |
| Typical planning date (30% risk) | Apr 28 | Oct 17 |
| Median (50%) | Apr 21 | Oct 23 |
How to read this: after the spring "10% risk" date, a 32°F frost happens in only about 1 year in 10. In fall, the "10% risk" date is the early end — a frost before it happens about 1 year in 10.
Frost data comes from NOAA station OGDEN PIONEER PH, UT (USC00426404), 1.6 mi (2.5 km) from the city center and 7 ft higher than the city center (+2 m). Record used for the 1991–2020 normals: 16 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across Ogden
Ogden spans more than one half-zone. Share of the city's land area by zone (via its 6 ZIP codes): 7a (75%), 6b (22%), 6a (3%). The headline zone is the one covering the most land. Look up your ZIP for your exact zone.
Vegetable planting calendar for Ogden
Dates are counted from the 30%-risk frost dates above (last frost Apr 28, first frost Oct 17). Shift a week later in cold spots or low-lying ground.
| Crop | Start indoors | Transplant / plant out | Direct sow | Fall crop sow/plant |
|---|---|---|---|---|
| Tomato | Mar 3 – Mar 17 | May 5 – May 19 | — | — |
| Pepper | Feb 17 – Mar 3 | May 12 – May 26 | — | — |
| Lettuce | Mar 17 – Mar 31 | Apr 14 – May 5 | Mar 31 – May 12 | Aug 8 – Sep 5 |
| Green Beans | — | — | May 5 – Jun 9 | Jul 25 – Aug 8 |
| Sweet Corn | — | — | May 5 – Jun 2 | — |
| Zucchini & Summer Squash | Mar 31 – Apr 7 | May 5 – May 19 | May 5 – May 26 | Jul 25 – Aug 8 |
| Cucumber | Mar 31 – Apr 7 | May 12 – May 19 | May 5 – May 26 | Jul 25 – Aug 8 |
| Carrot | — | — | Apr 7 – May 12 | Jul 25 – Aug 8 |
| Onion | Feb 3 – Feb 17 | Mar 31 – Apr 14 | — | — |
| Potato | — | Mar 31 – Apr 21 | — | — |
| Basil | Mar 17 – Mar 31 | May 12 – May 26 | May 12 – Jun 2 | — |
| Spinach | — | — | Mar 17 – Apr 14 | Aug 22 – Sep 19 |
| Kale | Mar 3 – Mar 17 | Mar 31 – Apr 21 | Mar 31 – Apr 21 | Aug 8 – Sep 5 |
| Broccoli | Mar 3 – Mar 17 | Apr 14 – May 5 | — | Jul 25 – Aug 8 |
| Peas | — | — | Mar 17 – Apr 7 | Aug 8 – Aug 22 |
| Eggplant | Feb 17 – Mar 3 | May 12 – May 26 | — | — |
| Cabbage | Mar 3 – Mar 17 | Mar 31 – Apr 14 | — | Jul 25 – Aug 8 |
| Radish | — | — | Mar 24 – May 12 | Sep 5 – Oct 3 |
| Strawberry | — | Mar 31 – Apr 21 | — | — |
| Beets | — | — | Apr 7 – May 19 | Aug 8 – Aug 22 |
Nearby cities in Utah
- Layton — zone 7a, last frost Apr 27, first frost Oct 13
- Salt Lake City — zone 7b, last frost Apr 16, first frost Oct 25
- West Valley City — zone 7b, last frost Apr 16, first frost Oct 25
- West Jordan — zone 7b, last frost Apr 25, first frost Oct 16
- Sandy — zone 7b, last frost May 8, first frost Oct 16
- South Jordan — zone 7a, last frost Apr 25, first frost Oct 16
More: all Utah cities · other zone 7a cities: Louisville, KY, Wichita, KS, Cleveland, OH, Lexington, KY, St. Louis, MO, Boise, ID, Amarillo, TX, Providence, RI
Ogden gardening questions
When is the last frost in Ogden, UT?
Plan around Apr 28. At NOAA's Ogden Pioneer Ph, UT station, 1.6 mi from the city center, there is a 30% chance of a 32°F frost after that date. Half of springs have their last frost by Apr 21, and after May 6 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Apr 5. The 90% and 10% dates are 34 days apart, close to the 36-day median for cities on this site.
When should I plant tomatoes in Ogden, UT?
Start seeds indoors Mar 3 – Mar 17 and set transplants outside May 5 – May 19, once nights stay above 50°F and the soil is near 60°F. That leaves 172 days between the 30% frost dates, enough for most varieties including 80–85-day slicers. More: tomato planting dates by zone.
How long is the growing season in Ogden?
About 184 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 162 days, and in 1 year in 10 it runs 208 days or more. In fall there is a 10% chance of frost by Oct 8 and a 30% chance by Oct 17. That ranks 7th longest of 11 Utah cities on this site.
When should I plant a fall garden in Ogden?
Count back from the first fall frost (Oct 17): transplant broccoli Jul 25 – Aug 8; sow kale Aug 8 – Sep 5; sow lettuce Aug 8 – Sep 5; sow radishes Sep 5 – Oct 3. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Nov 3. How the math works: succession and fall planting.
Did Ogden's hardiness zone change on the 2023 map?
Yes. Most of Ogden was zone 6b on the 2012 map and is zone 7a on the 2023 map — half a zone warmer, like about 56% of U.S. ZIP codes. The shift comes from a newer 1991–2020 averaging period plus more weather stations and better mapping; it does not mean last frost comes earlier. Why the 2023 map is warmer.
Is all of Ogden in zone 7a?
No. Zone 7a covers about 75% of the city's land; the rest is in 6b (22%), 6a (3%), measured across the city's 6 ZIP codes. Check your own ZIP code in the table above or with the ZIP lookup.