One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when it's possible to plant four-o-clock flower in San Antonio by reviewing the USDA zone info.

Planting Calendar for Four-o-clock flower

Frost tolerance for four-o-clock flower:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since four-o-clock flower require warm weather it is important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant four-o-clock flower in San Antonio 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 four-o-clock flower and expect a good harvest is probably August. Any later than that and your four-o-clock flower may not have a chance to fully mature. If you are starting your four-o-clock flower indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In San Antonio the average date of last frost happens on March 15. It might get as low as 15°F during the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for San Antonio and it is different every year. Half of the time in San Antonio you get a frost after March 15 so always be ready to cover your four-o-clock flower in the event of a late frost.

USDA Zone Info for San Antonio

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in San Antonio

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