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.

It's a good idea to estimate when it's a good idea to plant platycodon by referring to the USDA zone info for Suisun City.

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 do ok in moderate cold you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant platycodon in Suisun City 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. Any later than that and your platycodon may not have a chance to really do well. If you are starting your platycodon indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost is on February 15 in Suisun City. You should expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Suisun City is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Suisun City it frosts late in the year after February 15 be ready to protect your platycodon if you have one of those late frosts.

USDA Zone Info for Suisun City

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Suisun City

You may be interested in your other planting guides for Suisun City.