One of the best tools that you have as gardeners to help us figure out 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.

A common way of determining when it's the best time to plant skullcap is to look at the USDA zone info for Roma.

Planting Calendar for Skullcap

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

Since skullcap require warm weather you really should wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant skullcap in Roma 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. If you wait any later than that and your skullcap may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your skullcap indoors.

Last Frost Date

On average the last frost is on February 15 in Roma. In the coldest months of winter you should expect an average low temperature of 25°F.

Just be sure to remember that USDA zone info for Roma is just an average and the actual date of last frost will vary from year to year. Half of the time in Roma there is a last frost after February 15 so be sure to be ready to cover your skullcap if you have one of those late frosts.

USDA Zone Info for Roma

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 Roma

You may be interested in your other planting guides for Roma.