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 can determine when it's the best time to plant skullcap in San Bernardino by checking out the USDA zone info.

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 has passed before you can plant them.

The earliest that you can plant skullcap in San Bernardino 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 really do well. 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 Bernardino the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for San Bernardino may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in San Bernardino there is a last frost after February 15 be ready to cover your skullcap in the event of a surprise late frost.

USDA Zone Info for San Bernardino

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in San Bernardino

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