Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to determine when it's a good idea to plant yarrow by checking out the USDA zone info for Riverton.

Planting Calendar for Yarrow

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

You can plant yarrow a lot earlier in the year because they do well in cold.

The earliest that you can plant yarrow in Riverton 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 yarrow and expect a good harvest is probably August. If you wait any later than that and your yarrow may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your yarrow indoors.

Last Frost Date

On average the last frost is on May 15 in Riverton. It might get as low as -25°F during the coldest months of winter.

It's important to remember that USDA zone info for Riverton may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Riverton it frosts late in the year after May 15 be ready to protect your yarrow in the event of one of those late frosts.

USDA Zone Info for Riverton

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 Riverton

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