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

It's possible to determine when it's the best time to plant hardy hibiscus by using the USDA zone info for Riverton.

Planting Calendar for Hardy Hibiscus

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

You can plant hardy hibiscus earlier in the year because they are very cold tolerant.

The earliest that you can plant hardy hibiscus 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 hardy hibiscus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your hardy hibiscus may not have a chance to grow to maturity. If you are starting your hardy hibiscus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Riverton 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.

Keep in mind that USDA zone info for Riverton is just an average and the actual date of last frost is different every year. Since half of the time in Riverton last frost occurs after May 15 be ready to cover your hardy hibiscus in the event of a surprise late frost.

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.