Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of figuring out when you can plant ageratum is to consult the USDA zone info for Marshall.

Planting Calendar for Ageratum

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

You should not plant ageratum until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant ageratum in Marshall 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. You probably don't want to wait any later than that or else 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 little bit earlier.

Last Frost Date

In Marshall the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Marshall and it will vary from year to year. Half of the time in Marshall there is a last frost after April 15 so just be sure to be ready to protect your ageratum if you have one of those late frosts.

USDA Zone Info for Marshall

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 Marshall

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