One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In San Diego you can figure out when it's possible to plant pennyroyal by checking out the USDA zone info.

Planting Calendar for Pennyroyal

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

You can plant pennyroyal much earlier in the year because they do well in cold.

The earliest that you can plant pennyroyal in San Diego 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 pennyroyal and expect a good harvest is probably October. If you wait any later than that and your pennyroyal may not have a chance to really do well. You can get started a couple of weeks earlier by starting your pennyroyal indoors.

Last Frost Date

In San Diego the average date of last frost happens on January 31. You should expect an average low temperature of 35°F in the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for San Diego and it can change quite a bit from year to year. Since half of the time in San Diego you get a frost after January 31 be ready to cover your pennyroyal in the event of one of those late frosts.

USDA Zone Info for San Diego

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 San Diego

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