Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Cheyenne should be read to figure out when it's possible to plant sunflowers.

Planting Calendar for Sunflowers

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

You really shouldn't plant sunflowers until after all chance of frost has passed because they require warm weather.

The earliest that you can plant sunflowers in Cheyenne 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 grow to maturity. 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

On average the last frost has passed is on April 15 in Cheyenne. You can expect an average low temperature of -15°F in the coldest months of winter.

It's important to remember that USDA zone info for Cheyenne may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Cheyenne it frosts late in the year after April 15 be ready to protect your sunflowers if you have a surprise late frost.

USDA Zone Info for Cheyenne

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 Cheyenne

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