One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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 Jose should be estimated by referring to 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.

It's not a good idea to plant skullcap until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant skullcap in San Jose 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. Any later than that and your skullcap may not have a chance to fully mature. Starting your skullcap indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in San Jose. It might get as low as 25°F during the coldest months of winter.

Always keep in mind that USDA zone info for San Jose is an average and the actual date of last frost changes from year to year. Since half of the time in San Jose you get surprised by a frost after February 15 be ready to protect your skullcap in the event of a surprise late frost.

USDA Zone Info for San Jose

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 Jose

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