Before planting it is a good idea to find your USDA Zone info to determine 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.

A way of determining when it's possible to plant bidens is to check out the USDA zone info for Rock Springs.

Planting Calendar for Bidens

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

Since bidens require warm weather you really should wait until after the last frost before you can plant them.

The earliest that you can plant bidens in Rock Springs 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 bidens and expect a good harvest is probably August. If you wait any later than that and your bidens may not have a chance to really do well. You can get started a little bit earlier by starting your bidens indoors.

Last Frost Date

On average the last frost is on April 15 in Rock Springs. In the coldest months of winter you should expect an average low temperature of -20°F.

Just be sure to remember that USDA zone info for Rock Springs is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Rock Springs you get surprised by a frost after April 15 so always be ready to protect your bidens in the event of a late frost.

USDA Zone Info for Rock Springs

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Rock Springs

You may be interested in your other planting guides for Rock Springs.