One of the first steps you take when you are figuring out 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 getting a good idea when it's the best time to plant pentas is to look at the USDA zone info for San Bernardino.

Planting Calendar for Pentas

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

It's a bad idea to plant pentas until after the last frost because they require warm weather.

The earliest that you can plant pentas in San Bernardino 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 grow to maturity. If you are starting your pentas indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In San Bernardino the average date of last frost happens on February 15. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for San Bernardino is not always accurate the actual date of last frost changes from year to year. Since half of the time in San Bernardino you get a frost after February 15 be ready to protect your pentas in the event of one of those late frosts.

USDA Zone Info for San Bernardino

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 Bernardino

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