One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of estimating when it's a good idea to plant nasturtium is to examine the USDA zone info for Riverton.

Planting Calendar for Nasturtium

Frost tolerance for nasturtium:	Not tolerant of frost.
When to plant:	After the last frost.

It's probably not a good idea to plant nasturtium until after the last frost because they require warm weather.

The earliest that you can plant nasturtium in Riverton 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 nasturtium and expect a good harvest is probably August. If you wait any later than that and your nasturtium may not have a chance to fully mature. Starting your nasturtium indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost has passed is on May 15 in Riverton. You can expect an average low temperature of -25°F in 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 can change quite a bit from year to year. Since half of the time in Riverton you get surprised by a frost after May 15 be ready to cover your nasturtium 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.