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.

You can estimate when to plant skullcap in Scottsdale by looking at the USDA zone info.

Planting Calendar for Skullcap

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

You should not plant skullcap until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant skullcap in Scottsdale 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 little bit earlier by starting your skullcap indoors.

Last Frost Date

In Scottsdale the average date of last frost happens on February 15. You should expect an average low temperature of 25°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Scottsdale and it is different every year. Since half of the time in Scottsdale there is a last frost after February 15 be ready to cover your skullcap in the event of a late frost.

USDA Zone Info for Scottsdale

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 Scottsdale

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