One of the first steps you take when you are making a decision about 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 first opportunity to plant marigold in San Diego can be estimated by referring to the USDA zone info.

Planting Calendar for Marigold

Frost tolerance for marigold:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Marigold are not cold tolerant which tells us that you really should wait until it warms up after the last frost before you can plant them.

The earliest that you can plant marigold 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 marigold and expect a good harvest is probably September. You probably don't want to wait any later than that or else your marigold may not have a chance to really do well. If you are starting your marigold indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on February 15 in San Diego. It might get as low as 20°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for San Diego and it is different every year. Since half of the time in San Diego there is a last frost after February 15 be ready to cover your marigold 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.