One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Herndon should be reffered to in order to estimate when it's a good idea to plant skullcap.

Planting Calendar for Skullcap

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

Skullcap require warm weather which tells us that it's necessary to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant skullcap in Herndon 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 grow to maturity. You can get started a few weeks earlier by starting your skullcap indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Herndon. It might get as low as 0°F during the coldest months of winter.

It's important to remember that USDA zone info for Herndon is an average and the actual date of last frost will vary from year to year. Since half of the time in Herndon it frosts late in the year after April 15 be ready to protect your skullcap in the event of a surprise late frost.

USDA Zone Info for Herndon

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 Herndon

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