The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. 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 figuring out when to plant blue throatwort is to look at the USDA zone info for Rockville.

Planting Calendar for Blue Throatwort

Frost tolerance for blue throatwort:	Not tolerant of frost.
When to plant:	After the last frost.

Since blue throatwort require warm weather it is important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant blue throatwort in Rockville 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 blue throatwort and expect a good harvest is probably August. If you wait any later than that and your blue throatwort may not have a chance to fully mature. Starting your blue throatwort indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Rockville. In the coldest months of winter you can expect an average low temperature of 0°F.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Rockville and it is different every year. Since half of the time in Rockville there is a last frost after April 15 be ready to cover your blue throatwort if you have a surprise late frost.

USDA Zone Info for Rockville

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 Rockville

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