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

The best time to plant alternanthera in San Juan Capistrano should be determined by looking at the USDA zone info.

Planting Calendar for Alternanthera

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

It's probably not a good idea to plant alternanthera until after the last frost because they are not cold tolerant.

The earliest that you can plant alternanthera in San Juan Capistrano 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. If you wait any later than that and your alternanthera may not have a chance to grow to maturity. If you are starting your alternanthera indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is January 31 in San Juan Capistrano. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for San Juan Capistrano may not be accurate from year to year the actual date of last frost is different every year. Half of the time in San Juan Capistrano you get surprised by a frost after January 31 so be sure to be ready to protect your alternanthera in the event of one of those late frosts.

USDA Zone Info for San Juan Capistrano

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 San Juan Capistrano

You may be interested in your other planting guides for San Juan Capistrano.