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When to Plant Cardinal Flower in Winthrop Harbor, IL

Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Winthrop Harbor you can figure out when it's the best time to plant cardinal flower by reviewing the USDA zone info.


Planting Calendar for Cardinal Flower

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

Cardinal Flower do not do well in cold weather which means that it is important 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 cardinal flower
Possibly ok, but a risky time to plant cardinal flower
Probably not a good time to plant cardinal flower

The earliest that you can plant cardinal flower in Winthrop Harbor 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 cardinal flower and expect a good harvest is probably August. You probably don't want to wait any later than that or else your cardinal flower may not have a chance to fully mature. You can get started a little bit earlier by starting your cardinal flower indoors.

Last Frost Date

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

Since the USDA zone info for Winthrop Harbor is just an average the actual date of last frost is different every year. Since half of the time in Winthrop Harbor you get surprised by a frost after April 15 be ready to cover your cardinal flower if you have one of those late frosts.

USDA Zone Info for Winthrop Harbor

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 Winthrop Harbor

You may be interested in your other planting guides for Winthrop Harbor.