When to Plant Sunflowers in Vernon Hills, IL

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

The first chance to plant sunflowers in Vernon Hills can be figured out by using the USDA zone info.


Planting Calendar for Sunflowers

Frost tolerance for sunflowers: Not tolerant of frost.
When to plant: After the last frost has passed.

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

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 Vernon Hills 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. Any later than that and your sunflowers may not have a chance to fully mature. You can get started a little bit earlier by starting your sunflowers indoors.

Last Frost Date

The average date of last frost is April 15 in Vernon Hills. You should expect an average low temperature of -15°F in the coldest months of winter.

It's important to remember that USDA zone info for Vernon Hills is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Vernon Hills last frost occurs after April 15 so be sure to be ready to protect your sunflowers in the event of one of those late frosts.

USDA Zone Info for Vernon Hills

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 Vernon Hills

You may be interested in your other planting guides for Vernon Hills.