One of the first steps you take when you are getting a good idea 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.

You will be able to determine when you can plant four-o-clock flower by looking at the USDA zone info for San Bruno.

Planting Calendar for Four-o-clock flower

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

Since four-o-clock flower are not cold tolerant you must wait until after the last frost has passed before you can plant them.

The earliest that you can plant four-o-clock flower in San Bruno 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 four-o-clock flower and expect a good harvest is probably September. Any later than that and your four-o-clock flower may not have a chance to really do well. Starting your four-o-clock flower indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for San Bruno and it is different every year. Since half of the time in San Bruno there is a last frost after January 31 be ready to cover your four-o-clock flower in the event of one of those late frosts.

USDA Zone Info for San Bruno

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 Bruno

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