One of the first steps you take when you are figuring out your gardening schedule is find your 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.

By referring to the USDA zone info for Norman you should be able to estimate when it's the best time to plant skullcap.

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 has passed because they are not cold tolerant.

The earliest that you can plant skullcap in Norman is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant skullcap and expect a good harvest is probably August. Any later than that and your skullcap may not have a chance to fully mature. You can get started a few weeks earlier by starting your skullcap indoors.

Last Frost Date

The average date of last frost is April 15 in Norman. In the coldest months of winter you should expect an average low temperature of 0°F.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Norman and it changes from year to year. Half of the time in Norman you get surprised by a frost after April 15 so make sure that you are ready to protect your skullcap in the event of a surprise late frost.

USDA Zone Info for Norman

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Norman

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