Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of making a decision about when it's a good idea to plant pentas is to use the USDA zone info for San Ramon.

Planting Calendar for Pentas

Frost tolerance for pentas:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

You should not plant pentas until after the last frost because they are not cold tolerant.

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

Last Frost Date

The average date of last frost is February 15 in San Ramon. You should expect an average low temperature of 25°F in the coldest months of winter.

Just be sure to remember that USDA zone info for San Ramon may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in San Ramon you get a frost after February 15 be ready to cover your pentas if you have a late frost.

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.