When to plant in Alta Sierra, CA
Planting dates worked out from Alta Sierra's own frost records, not a generic zone chart.
Safe to plant out
May 26
1 year in 10 has a later frost
Average last frost
May 2
about a 50% chance of a later one
Average first fall frost
Nov 4
1 year in 10 by Oct 9
Frost-free days
185
median, 1991–2020
Station used: Walker Pass California · 45.5 km away · station 1698 m, town 1743 m. How we match towns to stations
The nearest reliable station is 46 km away, so frost dates here may be off by a week or more. Check them against local experience.
This season
Plan your garden.
Planting dates for common crops
| Crop | Start indoors | Plant out or sow | Harvest from |
|---|---|---|---|
| Tomato | Mar 31 – Apr 14 | May 26 – Jun 9 | Jul 20 |
| Sweet pepper | Mar 17 – Mar 31 | May 26 – Jun 9 | Jul 25 |
| Lettuce (leaf) | Feb 28 – Mar 7 | Apr 4 – Apr 18 | May 14 |
| Peas | — | Mar 21 – Apr 18 | May 15 |
| Bush beans | — | May 19 – Jun 9 | Jul 8 |
| Carrot | — | Apr 11 – May 23 | Jun 10 |
| Beet | — | Apr 4 – May 16 | May 24 |
| Potato | — | Apr 11 – May 2 | Jun 20 |
| Kale | Feb 21 – Mar 7 | Apr 4 – Apr 18 | May 17 |
| Broccoli | Feb 21 – Mar 7 | Apr 4 – Apr 25 | Jun 3 |
| Cucumber | Apr 28 – May 5 | May 26 – Jun 9 | Jul 15 |
| Summer squash and zucchini | Apr 28 – May 5 | May 26 – Jun 9 | Jul 10 |
| Winter squash | Apr 28 – May 5 | May 26 – Jun 9 | Aug 14 |
| Sweet corn | — | May 19 – Jun 9 | Jul 18 |
| Onion (from sets) | — | Apr 4 – Apr 25 | Jul 3 |
| Garlic | — | Oct 21 – Nov 18 (fall) | following summer |
| Spinach | — | Mar 21 – Apr 18 | Apr 28 |
| Basil | Apr 14 – Apr 28 | May 26 – Jun 9 | Jul 22 |
Alta Sierra's weather over time
How the growing season has shifted here, year by year, from the station's own records.
Each year's last spring frostLong-term trend
See the data as a table
| Year | Last spring frost |
|---|---|
| 1992 | Mar 23 |
| 1993 | Apr 12 |
| 1994 | Apr 26 |
| 1995 | May 15 |
| 1996 | Apr 21 |
| 1997 | Apr 24 |
| 1998 | May 27 |
| 1999 | Apr 29 |
| 2000 | May 16 |
| 2001 | Apr 22 |
| 2002 | May 21 |
| 2003 | May 10 |
| 2004 | Apr 18 |
| 2005 | May 10 |
| 2006 | Apr 18 |
| 2007 | May 5 |
| 2008 | Apr 21 |
| 2009 | Apr 29 |
| 2010 | May 24 |
| 2011 | May 30 |
| 2012 | May 26 |
| 2013 | Apr 17 |
| 2014 | Apr 26 |
| 2015 | May 8 |
| 2016 | Apr 26 |
| 2017 | May 7 |
| 2018 | Apr 19 |
| 2019 | May 27 |
| 2020 | Apr 9 |
| 2021 | Mar 26 |
| 2022 | Apr 22 |
| 2023 | May 4 |
| 2024 | May 6 |
Each year's frost-free daysLong-term trend
See the data as a table
| Year | Frost-free days |
|---|---|
| 1992 | 230 |
| 1993 | 213 |
| 1994 | 189 |
| 1995 | 195 |
| 1996 | 180 |
| 1997 | 169 |
| 1998 | 162 |
| 1999 | 205 |
| 2000 | 166 |
| 2001 | 203 |
| 2002 | 203 |
| 2003 | 172 |
| 2004 | 185 |
| 2005 | 199 |
| 2006 | 206 |
| 2007 | 152 |
| 2008 | 171 |
| 2009 | 157 |
| 2010 | 167 |
| 2011 | 129 |
| 2012 | 166 |
| 2013 | 175 |
| 2014 | 190 |
| 2015 | 178 |
| 2016 | 203 |
| 2017 | 203 |
| 2018 | 225 |
| 2019 | 155 |
| 2020 | 211 |
| 2021 | 199 |
| 2022 | 193 |
| 2023 | 199 |
| 2024 | 189 |
Each year's average temperature, April to SeptemberLong-term trend
See the data as a table
| Year | Growing-season temperature |
|---|---|
| 1992 | 20.9 °C |
| 1993 | 19.7 °C |
| 1994 | 20.6 °C |
| 1995 | 18.6 °C |
| 1996 | 20.9 °C |
| 1997 | 20.2 °C |
| 1998 | 18.2 °C |
| 1999 | 18.9 °C |
| 2000 | 20.8 °C |
| 2001 | 21.1 °C |
| 2002 | 21.0 °C |
| 2003 | 20.7 °C |
| 2004 | 20.7 °C |
| 2005 | 19.9 °C |
| 2006 | 20.8 °C |
| 2007 | 20.8 °C |
| 2008 | 20.5 °C |
| 2009 | 20.7 °C |
| 2010 | 19.3 °C |
| 2011 | 19.3 °C |
| 2012 | 21.5 °C |
| 2013 | 20.9 °C |
| 2014 | 21.2 °C |
| 2015 | 20.7 °C |
| 2016 | 20.8 °C |
| 2017 | 20.6 °C |
| 2018 | 21.1 °C |
| 2019 | 19.2 °C |
| 2020 | 20.6 °C |
| 2021 | 22.1 °C |
| 2022 | 21.0 °C |
| 2023 | 19.0 °C |
| 2024 | 20.8 °C |
What this means for you: Since 1992, Alta Sierra's last spring frost has stayed at about the same time of year. Year-to-year swings are large, so keep using the safe date rather than the trend.
Source: daily records from Walker Pass California (NOAA GHCN-Daily). Years with too many missing days are left out.