The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for San Rafael can be reffered to in order to estimate when it's a good idea to plant skullcap.

Planting Calendar for Skullcap

Frost tolerance for skullcap:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since skullcap require warm weather it's necessary to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant skullcap in San Rafael 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 skullcap and expect a good harvest is probably September. If you wait any later than that and your skullcap may not have a chance to grow to maturity. If you are starting your skullcap indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In San Rafael the average date of last frost happens on January 31. In the coldest months of winter you should expect an average low temperature of 30°F.

Since the USDA zone info for San Rafael may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in San Rafael last frost occurs after January 31 be ready to protect your skullcap if you have a surprise late frost.

USDA Zone Info for San Rafael

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 San Rafael

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