One of the first steps you take when you are making a decision about 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.

It's a good idea to determine when to plant alternanthera by using the USDA zone info for Hannibal.

Planting Calendar for Alternanthera

Frost tolerance for alternanthera:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Alternanthera are not cold tolerant which tells us that you really should wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant alternanthera in Hannibal 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 alternanthera and expect a good harvest is probably August. Any later than that and your alternanthera may not have a chance to really do well. You can get started a few weeks earlier by starting your alternanthera indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Hannibal. You can expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Hannibal may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Hannibal last frost occurs after April 15 so always be ready to cover your alternanthera if you have a late frost.

USDA Zone Info for Hannibal

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 Hannibal

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