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.

A way of figuring out when it's a good idea to plant ageratum is to use the USDA zone info for Forest Lake.

Planting Calendar for Ageratum

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

Since ageratum require warm weather you need to wait until after the last frost has passed before you can plant them.

The earliest that you can plant ageratum in Forest Lake 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. Starting your ageratum indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Forest Lake. It might get as low as -25°F during the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Forest Lake and it can change quite a bit from year to year. Since half of the time in Forest Lake there is a last frost after May 15 be ready to cover your ageratum if you have one of those late frosts.

USDA Zone Info for Forest Lake

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Forest Lake

You may be interested in your other planting guides for Forest Lake.