One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to determine when it's the best time to plant ageratum by checking out the USDA zone info for Rock Springs.

Planting Calendar for Ageratum

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

Ageratum do not do well in cold weather which means that you really should wait until it warms up after the last frost before you can plant them.

The earliest that you can plant ageratum 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 ageratum and expect a good harvest is probably August. Any later than that and your ageratum may not have a chance to really do well. Starting your ageratum indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Rock Springs. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Rock Springs is not always accurate the actual date of last frost will vary from year to year. Half of the time in Rock Springs there is a last frost after April 15 so make sure that you are ready to protect your ageratum if you have a surprise 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.