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.

The USDA zone info for Signal Hill should be reviewed to estimate when you can plant calibrachoa.

Planting Calendar for Calibrachoa

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

Calibrachoa do well in a tiny bit of cold which means that you can plant them slightly earlier in the year than other plants that might not handle the cold.

The earliest that you can plant calibrachoa 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 calibrachoa and expect a good harvest is probably September. Any later than that and your calibrachoa may not have a chance to grow to maturity. If you are starting your calibrachoa indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Signal Hill the average date of last frost happens on January 31. You can expect an average low temperature of 35°F in the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Signal Hill and it changes from year to year. Since half of the time in Signal Hill you get a frost after January 31 be ready to protect your calibrachoa in the event of a surprise late frost.

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.