When to Plant Sunflowers in Wilmette, IL

One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Wilmette should be looked at to figure out when to plant sunflowers.


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 when the weather gets warmer because they require warm 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 Wilmette 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 little bit earlier.

Last Frost Date

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

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Wilmette and it is different every year. Half of the time in Wilmette there is a last frost after April 15 so make sure that you are ready to protect your sunflowers if you have one of those late frosts.

USDA Zone Info for Wilmette

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 Wilmette

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