One of the first steps you take when you are getting a good idea your gardening schedule is find your 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.

The USDA zone info for Napa should be used to determine when it's the best time to plant pentas.

Planting Calendar for Pentas

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

Pentas require warm weather which means that you really should wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant pentas in Napa 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. Any later than that and your pentas may not have a chance to really do well. If you are starting your pentas indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in Napa. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Napa is just an average the actual date of last frost is different every year. Since half of the time in Napa you get surprised by a frost after February 15 be ready to protect your pentas in the event of a surprise late frost.

USDA Zone Info for Napa

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 Napa

You may be interested in your other planting guides for Napa.