Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant black eyed susans in San Diego can be estimated by looking at the USDA zone info.

Planting Calendar for Black Eyed Susans

Frost tolerance for black eyed susans:	Not tolerant of frost.
When to plant:	After the last frost.

It's not a good idea to plant black eyed susans until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant black eyed susans in San Diego 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 black eyed susans and expect a good harvest is probably September. You probably don't want to wait any later than that or else your black eyed susans may not have a chance to grow to maturity. Starting your black eyed susans indoors is a great way to get them started a little bit earlier.

Last Frost Date

In San Diego the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 20°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for San Diego and it is different every year. Half of the time in San Diego there is a last frost after February 15 so make sure that you are ready to protect your black eyed susans if you have one of those late frosts.

USDA Zone Info for San Diego

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in San Diego

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