One of the best tools that you have as gardeners to help us figure out 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.

The best time to plant ageratum in Andover should be figured out by reviewing the USDA zone info.

Planting Calendar for Ageratum

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

It's a bad idea to plant ageratum until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant ageratum in Andover 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. You probably don't want to wait any later than that or else your ageratum may not have a chance to fully mature. 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

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

Since the USDA zone info for Andover is not always accurate the actual date of last frost is different every year. Half of the time in Andover you get surprised by a frost after May 15 so just be sure to be ready to protect your ageratum in the event of one of those late frosts.

USDA Zone Info for Andover

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 Andover

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