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.

You can estimate when you can plant skullcap in Andover by referring to 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.

Skullcap are not cold tolerant which tells us that you must wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant skullcap in Andover is May. However, you really should wait until June 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 couple of weeks earlier by starting your skullcap indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Andover. You can expect an average low temperature of -25°F in the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Andover and it can change quite a bit from year to year. Half of the time in Andover it frosts late in the year after May 15 so make sure that you are prepared to protect your skullcap if you have one of those late frosts.

USDA Zone Info for Andover

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°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 -20°F.

Plants to Grow in Andover

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