Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Signal Hill should be read to estimate when it's possible to plant petunias.

Planting Calendar for Petunias

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

You can plant petunias just a tiny bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant petunias in Signal Hill 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. If you wait any later than that and your petunias may not have a chance to grow to maturity. If you are starting your petunias indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Signal Hill. It might get as low as 35°F during the coldest months of winter.

Since the USDA zone info for Signal Hill is just an average the actual date of last frost changes from year to year. Half of the time in Signal Hill last frost occurs after January 31 so just be sure to be ready to protect your petunias if you have one of those late frosts.

USDA Zone Info for Signal Hill

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in Signal Hill

You may be interested in your other planting guides for Signal Hill.