When to Plant Sunflowers in University Park, IL

One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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 first opportunity to plant sunflowers in University Park can be figured out by reviewing the USDA zone info.


Planting Calendar for Sunflowers

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

Sunflowers are not cold tolerant which tells us that you really should wait until it warms up after the last frost has passed before you can plant them.

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

The earliest that you can plant sunflowers in University Park 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 sunflowers and expect a good harvest is probably August. You probably don't want to wait any later than that or else your sunflowers may not have a chance to really do well. Starting your sunflowers indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in University Park. In the coldest months of winter you can expect an average low temperature of 5°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for University Park and it will vary from year to year. Since half of the time in University Park last frost occurs after April 15 be ready to protect your sunflowers in the event of a late frost.

USDA Zone Info for University Park

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low5°F
Highest Expected Low10°F

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

Plants to Grow in University Park

You may be interested in your other planting guides for University Park.