One of the first steps you take when you are determining 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.

A way of figuring out when it's the best time to plant begonias is to use the USDA zone info for San Bruno.

Planting Calendar for Begonias

Frost tolerance for begonias:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Begonias do not do well in cold weather which tells us that you have to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant begonias 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 begonias and expect a good harvest is probably September. You probably don't want to wait any later than that or else your begonias may not have a chance to fully mature. If you are starting your begonias indoors then you might be able to get away with starting them a couple of weeks 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.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for San Bruno and it is different every year. Half of the time in San Bruno there is a last frost after January 31 so just be sure to be ready to protect your begonias if you have a late frost.

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.