The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Calexico can be looked at to figure out when it's possible to plant alternanthera.

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 require warm weather which means that you have to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant alternanthera in Calexico is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant alternanthera and expect a good harvest is probably September. You probably don't want to wait any later than that or else your alternanthera may not have a chance to fully mature. Starting your alternanthera indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Calexico. It might get as low as 30°F during the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Calexico and it is different every year. Half of the time in Calexico there is a last frost after January 31 so be sure to be ready to cover your alternanthera in the event of one of those late frosts.

USDA Zone Info for Calexico

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Calexico

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