The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Rifle should be reffered to in order to figure out when you can plant ageratum.

Planting Calendar for Ageratum

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

It's a bad idea to plant ageratum until after the last frost because they do not do well in cold weather.

The earliest that you can plant ageratum in Rifle 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. You probably don't want to wait any later than that or else your ageratum may not have a chance to really do well. Starting your ageratum indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Rifle. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Rifle is not always accurate the actual date of last frost changes from year to year. Since half of the time in Rifle you get a frost after April 15 be ready to cover your ageratum in the event of a surprise late frost.

USDA Zone Info for Rifle

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Rifle

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