Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when you can plant lemon balm in South San Francisco by reviewing the USDA zone info.

Planting Calendar for Lemon balm

Frost tolerance for lemon balm:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Lemon balm can survive in some cold which tells us that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant lemon balm in South San Francisco is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant lemon balm and expect a good harvest is probably September. Any later than that and your lemon balm may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your lemon balm indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in South San Francisco. In the coldest months of winter you should expect an average low temperature of 30°F.

Keep in mind that USDA zone info for South San Francisco is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in South San Francisco it frosts late in the year after January 31 so always be ready to cover your lemon balm in the event of a late frost.

USDA Zone Info for South San Francisco

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 South San Francisco

You may be interested in your other planting guides for South San Francisco.