One of the first steps you take when you are estimating your gardening schedule is find your 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.

The earliest that you can plant skullcap in San Diego can be figured out by checking out the USDA zone info.

Planting Calendar for Skullcap

Frost tolerance for skullcap:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since skullcap are not cold tolerant you must wait until after the last frost before you can plant them.

The earliest that you can plant skullcap in San Diego is March. However, you really should wait until April if you don't want to take any chances.

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

Last Frost Date

The average date of last frost is February 15 in San Diego. In the coldest months of winter you can expect an average low temperature of 20°F.

Remember 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 last frost occurs after February 15 be ready to protect your skullcap if you have a late frost.

USDA Zone Info for San Diego

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in San Diego

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