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.

You can estimate when it's the best time to plant blue throatwort in Waterloo by looking at the USDA zone info.

Planting Calendar for Blue Throatwort

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

It's a bad idea to plant blue throatwort until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant blue throatwort in Waterloo 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. You can get started a few weeks earlier by starting your blue throatwort indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Waterloo. In the coldest months of winter you can expect an average low temperature of -20°F.

Always keep in mind that USDA zone info for Waterloo is not always accurate and the actual date of last frost changes from year to year. Half of the time in Waterloo there is a last frost after April 15 so just be sure to be ready to cover your blue throatwort if you have one of those late frosts.

USDA Zone Info for Waterloo

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Waterloo

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