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

You can estimate when it's a good idea to plant dianthus in South San Francisco by reviewing the USDA zone info.

Planting Calendar for Dianthus

Frost tolerance for dianthus:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Dianthus are moderately cold tolerant which tells us that you can plant them earlier than plants that are more sensitive to the cold.

The earliest that you can plant dianthus in South San Francisco is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant dianthus and expect a good harvest is probably October. Any later than that and your dianthus may not have a chance to grow to maturity. If you are starting your dianthus indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on January 31 in South San Francisco. In the coldest months of winter you can expect an average low temperature of 30°F.

Since the USDA zone info for South San Francisco is an average the actual date of last frost can change quite a bit from year to year. Half of the time in South San Francisco there is a last frost after January 31 so make sure that you are prepared to protect your dianthus in the event of a late frost.

USDA Zone Info for South San Francisco

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in South San Francisco

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