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

A way of figuring out when you can plant ageratum is to consult the USDA zone info for Presque Isle.

Planting Calendar for Ageratum

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

Ageratum are not cold tolerant which tells us that it's necessary to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant ageratum in Presque Isle 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 grow to maturity. Starting your ageratum indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on May 15 in Presque Isle. In the coldest months of winter you should expect an average low temperature of -30°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Presque Isle and it changes from year to year. Since half of the time in Presque Isle it frosts late in the year after May 15 be ready to protect your ageratum if you have a late frost.

USDA Zone Info for Presque Isle

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Presque Isle

You may be interested in your other planting guides for Presque Isle.