One of the first steps you take when you are getting a good idea 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.

The first opportunity to plant ageratum in Zone 2a should be determined by looking at the USDA zone info.

Planting Calendar for Ageratum

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

You can not plant ageratum until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant ageratum in Zone 2a 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 ageratum and expect a good harvest is probably August. If you wait any later than that and your ageratum may not have a chance to really do well. If you are starting your ageratum indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on May 15 in Zone 2a. You should expect an average low temperature of -50°F in the coldest months of winter.

Remember that USDA zone info for Zone 2a is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Zone 2a there is a last frost after May 15 be ready to protect your ageratum if you have a surprise late frost.

USDA Zone Info for Zone 2a

Here is the info for USDA Zone 2a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	August 15
Lowest Expected Low	-50°F
Highest Expected Low	-45°F

This means that on a really cold year, the coldest it will get is -50°F. On most years you should be prepared to experience lows near -45°F.

Plants to Grow in Zone 2a

You may be interested in your other planting guides for Zone 2a.