When to Plant Sunflowers in Wausau, WI

The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant sunflowers in Wausau should be determined by using the USDA zone info.


Planting Calendar for Sunflowers

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

You really shouldn't 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 Wausau is May. However, you really should wait until June 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. If you wait any later than that and your sunflowers may not have a chance to really do well. If you are starting your sunflowers indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Wausau the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -25°F.

Just be sure to remember that USDA zone info for Wausau is just an average and the actual date of last frost will vary from year to year. Half of the time in Wausau it frosts late in the year after May 15 so just be sure to be ready to cover your sunflowers in the event of a late frost.

USDA Zone Info for Wausau

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-25°F
Highest Expected Low-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Wausau

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