The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to figure out when you can plant begonias by looking at the USDA zone info for San Jose.

Planting Calendar for Begonias

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

You really shouldn't plant begonias until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant begonias in San Jose is March. However, you really should wait until April 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. If you wait any later than that and your begonias may not have a chance to grow to maturity. 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

On average the last frost is on February 15 in San Jose. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for San Jose is just an average the actual date of last frost is different every year. Since half of the time in San Jose you get a frost after February 15 be ready to cover your begonias if you have a surprise late frost.

USDA Zone Info for San Jose

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in San Jose

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