Frost dates for 84333Richmond, UT
The average last spring frost in Richmond is May 11 and the average first fall frost is October 5, giving a typical growing season of about 143 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 11
- Average first fall frost
- Oct 5
- Growing season
- 143 days
Safer after Jun 2 (1-in-10 risk)
Possible by Sep 21 (1-in-10 risk)
Last frost typically in 196 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | May 12 · May 31 · Jun 15 | Sep 10 · Sep 24 · Oct 7 | 116 days | 100% |
| Frost / freeze (32°F) | Apr 27 · May 11 · Jun 2 | Sep 21 · Oct 5 · Oct 20 | 143 days | 100% |
| Hard freeze (28°F) | Apr 8 · Apr 26 · May 13 | Oct 1 · Oct 17 · Nov 1 | 172 days | 100% |
Planting calendar for Richmond
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Apr 10 – Jun 16 |
| Tomatoes | Transplant outdoors | May 27 – Jun 15 |
| Peppers | Start seeds indoors | Apr 10 – May 11 |
| Peppers | Transplant outdoors | Jun 10 – Jul 11 |
| Eggplant | Start seeds indoors | Apr 27 – May 26 |
| Eggplant | Transplant outdoors | Jun 10 – Jul 11 |
| Cucumbers | Sow outdoors | Jun 10 – Jun 25 |
| Summer squash | Sow outdoors | May 27 – Jul 11 |
| Winter squash & pumpkins | Sow outdoors | Jun 10 – Jul 11 |
| Snap beans | Sow outdoors | May 27 – Jul 18 |
| Sweet corn | Sow outdoors | May 27 – Jun 15 |
| Watermelon & cantaloupe | Sow outdoors | Jun 10 – Jul 11 |
| Okra | Sow outdoors | Jun 3 – Jun 26 |
| Peas | Sow outdoors (spring) | Apr 10 – May 26 |
| Potatoes | Plant outdoors (spring) | Apr 10 – Jun 10 |
| Onions | Start seeds indoors (spring) | Feb 27 – Mar 26 |
| Onions | Transplant outdoors (spring) | Apr 27 – May 26 |
| Broccoli | Start seeds indoors (spring) | Mar 23 – Apr 26 |
| Broccoli | Transplant outdoors (spring) | Apr 27 – May 26 |
| Broccoli | Start seeds indoors (fall) | Jun 5 – Jun 15 |
| Broccoli | Transplant outdoors (fall) | Jul 5 – Jul 16 |
| Cabbage | Start seeds indoors (spring) | Mar 13 – Apr 10 |
| Cabbage | Transplant outdoors (spring) | Apr 10 – May 11 |
| Cabbage | Start seeds indoors (fall) | May 26 – Jun 25 |
| Cabbage | Transplant outdoors (fall) | Jun 25 – Jul 26 |
| Leaf lettuce | Sow outdoors (spring) | Apr 10 – Jun 26 |
| Leaf lettuce | Sow outdoors (fall) | Jun 25 – Aug 11 |
| Spinach | Sow outdoors (spring) | Apr 3 – May 17 |
| Spinach | Sow outdoors (fall) | Jul 12 – Aug 16 |
| Radishes | Sow outdoors (spring) | Apr 10 – May 31 |
| Radishes | Sow outdoors (fall) | Jun 25 – Aug 26 |
| Kale | Sow outdoors (spring) | Apr 27 – May 17 |
| Kale | Sow outdoors (fall) | Jun 18 – Jul 26 |
| Carrots | Sow outdoors (spring) | May 11 – Jun 26 |
| Carrots | Sow outdoors (fall) | May 26 – Jul 11 |
| Garlic | Plant outdoors (fall) | Sep 25 – Oct 26 |
Where these dates come from
ZIP code 84333 is matched to the NOAA station Richmond, UT, 2.4 km away, at 4,680 ft elevation (54 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Richmond, UT (used) | 4,680 ft | May 11 | Oct 5 |
| Trenton, UT | 4,455 ft | May 17 | Sep 18 |
| Logan Cache Ap, UT | 4,454 ft | May 8 | Oct 2 |
| Preston, ID | 4,719 ft | May 16 | Sep 28 |
Frost dates near Richmond
- Lewiston, UT 84320 · last May 17, first Sep 18
- Smithfield, UT 84335 · last May 8, first Oct 2
- Trenton, UT 84338 · last May 17, first Sep 18
- Franklin, ID 83237 · last May 16, first Sep 28
- Cornish, UT 84308 · last May 17, first Sep 18
- Hyde Park, UT 84318 · last May 8, first Oct 2
- Newton, UT 84327 · last May 17, first Sep 18
- Logan, UT 84341 · last Apr 30, first Oct 16
Frequently asked questions
- When is the last frost in Richmond, UT?
- For ZIP code 84333, the average last spring frost (32°F) is May 11, based on NOAA 1991-2020 climate normals for the Richmond, UT weather station. There is a 1-in-10 chance of a frost after June 2.
- When is the first frost in Richmond, UT?
- The average first fall frost (32°F) is October 5. There is a 1-in-10 chance of frost by September 21, so tender plants are at risk from that point on.
- How long is the growing season in 84333?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 143 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.