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When to Plant Blue Throatwort in Marengo, IL

One of the first steps you take when you are figuring out your gardening schedule is find your 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.

The USDA zone info for Marengo should be used to estimate when to plant blue throatwort.


Planting Calendar for Blue Throatwort

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

Blue Throatwort are not cold tolerant which means that it is necessary to wait until it warms up after all chance of frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant blue throatwort
Possibly ok, but a risky time to plant blue throatwort
Probably not a good time to plant blue throatwort

The earliest that you can plant blue throatwort in Marengo 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 grow to maturity. If you are starting your blue throatwort indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

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 Marengo and it will vary from year to year. Half of the time in Marengo last frost occurs after April 15 so just be sure to be ready to protect your blue throatwort in the event of a late frost.

USDA Zone Info for Marengo

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Marengo

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