One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Upland you can estimate when to plant sorrel by looking at the USDA zone info.

Planting Calendar for Sorrel

Frost tolerance for sorrel:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Sorrel do well in moderate cold which means that you can plant them earlier than more sensitive plants.

The earliest that you can plant sorrel in Upland is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant sorrel and expect a good harvest is probably October. You probably don't want to wait any later than that or else your sorrel may not have a chance to fully mature. You can get started a few weeks earlier by starting your sorrel indoors.

Last Frost Date

In Upland the average date of last frost happens on January 31. You can expect an average low temperature of 30°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Upland is an average and the actual date of last frost changes from year to year. Since half of the time in Upland last frost occurs after January 31 be ready to protect your sorrel in the event of a late frost.

USDA Zone Info for Upland

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Upland

You may be interested in your other planting guides for Upland.