One of the first steps you take when you are getting a good idea 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.

You will be able to estimate when it's a good idea to plant platycodon by referring to the USDA zone info for San Diego.

Planting Calendar for Platycodon

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

Since platycodon are one of those plants that can tolerate a tiny bit of cold weather you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

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

Last Frost Date

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

Keep in mind that USDA zone info for San Diego is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in San Diego there is a last frost after January 31 be ready to cover your platycodon in the event of a surprise late frost.

USDA Zone Info for San Diego

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 San Diego

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