When to Plant Sunflowers in Gillette, WY

The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Gillette you can estimate when you can plant sunflowers 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.

It's 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 Gillette 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. You probably don't want to wait any later than that or else your sunflowers may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your sunflowers indoors.

Last Frost Date

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

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Gillette and it is different every year. Since half of the time in Gillette it frosts late in the year after May 15 be ready to cover your sunflowers in the event of a surprise late frost.

USDA Zone Info for Gillette

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 Gillette

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