The USDA Zone info is a great tool for gardeners to help us determine 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.

The USDA zone info for Hillsboro should be read to figure out when you can plant blue throatwort.

Planting Calendar for Blue Throatwort

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

It's probably not a good idea to plant blue throatwort until after the last frost has passed because they do not do well in cold weather.

The earliest that you can plant blue throatwort in Hillsboro 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. You probably don't want to wait any later than that or else your blue throatwort may not have a chance to really do well. Starting your blue throatwort indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Hillsboro the average date of last frost happens on April 15. You should expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Hillsboro may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Hillsboro you get surprised by a frost after April 15 so be sure to be ready to protect your blue throatwort in the event of a surprise late frost.

USDA Zone Info for Hillsboro

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Hillsboro

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