When can I plant Petunias in Zone 9b

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

By looking at the USDA zone info for Zone 9b it's a good idea to figure out when it's the best time to plant petunias.


Planting Calendar for Petunias

Frost tolerance for petunias: Tolerant of a very small amount of frost.
When you should plant them: Up to 3 weeks before last frost.

Since petunias do ok in moderate cold you can plant them slightly earlier in the year than other frost tender plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant petunias
Possibly ok, but a risky time to plant petunias
Probably not a good time to plant petunias

The earliest that you can plant petunias in Zone 9b is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant petunias and expect a good harvest is probably September. Any later than that and your petunias may not have a chance to really do well. Starting your petunias indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Zone 9b. In the coldest months of winter we should expect an average low temperature of 25°F.

Remember that our actual date of last frost is an average because it is based on the USDA zone info for Zone 9b and it can change quite a bit from year to year. Half of the time in Zone 9b we get a frost after February 15 so be sure to be ready to cover your petunias in the event of a surprise late frost.

USDA Zone Info for Zone 9b

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 Low25°F
Highest Expected Low30°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 Zone 9b

You may be interested in our other planting guides for Zone 9b.