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.

By using the USDA zone info for Green River you will be able to estimate when it's a good idea to plant gayfeather.

Planting Calendar for Gayfeather

Frost tolerance for gayfeather:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

You can plant gayfeather much earlier in the year because they do well in cold.

The earliest that you can plant gayfeather in Green River is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant gayfeather and expect a good harvest is probably August. You probably don't want to wait any later than that or else your gayfeather may not have a chance to grow to maturity. Starting your gayfeather indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on May 15 in Green River. You can expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Green River is an average the actual date of last frost will vary from year to year. Half of the time in Green River last frost occurs after May 15 so make sure that you are ready to protect your gayfeather in the event of one of those late frosts.

USDA Zone Info for Green River

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 Green River

You may be interested in your other planting guides for Green River.