One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to figure out when you can plant spearmint by checking out the USDA zone info for National City.

Planting Calendar for Spearmint

Frost tolerance for spearmint:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Spearmint do well in cold which means that you can start planting them much earlier than plants that are more sensitive to the cold.

The earliest that you can plant spearmint in National City 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 spearmint and expect a good harvest is probably October. Any later than that and your spearmint may not have a chance to grow to maturity. Starting your spearmint indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is January 31 in National City. You should expect an average low temperature of 35°F in the coldest months of winter.

Since the USDA zone info for National City may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in National City you get a frost after January 31 be ready to cover your spearmint if you have one of those late frosts.

USDA Zone Info for National City

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in National City

You may be interested in your other planting guides for National City.