One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of estimating when to plant ageratum is to use the USDA zone info for Portage.

Planting Calendar for Ageratum

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

It's probably a bad idea to plant ageratum until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant ageratum in Portage 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. If you are starting your ageratum indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Portage. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Portage is just an average the actual date of last frost changes from year to year. Since half of the time in Portage last frost occurs after April 15 be ready to cover your ageratum in the event of a surprise late frost.

USDA Zone Info for Portage

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Portage

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