One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to determine when you can plant tithonia by checking out the USDA zone info for San Ramon.

Planting Calendar for Tithonia

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

Tithonia require warm weather which tells us that you really should wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant tithonia in San Ramon 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 tithonia and expect a good harvest is probably September. You probably don't want to wait any later than that or else your tithonia may not have a chance to really do well. You can get started a few weeks earlier by starting your tithonia indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in San Ramon. In the coldest months of winter you can expect an average low temperature of 25°F.

Since the USDA zone info for San Ramon is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in San Ramon there is a last frost after February 15 be ready to protect your tithonia if you have one of those late frosts.

USDA Zone Info for San Ramon

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 Ramon

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