Before planting it is a good idea to find your USDA Zone info to estimate 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.

A way of making a decision about when it's possible to plant balloon flower is to consult the USDA zone info for San Francisco.

Planting Calendar for Balloon Flower

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

You can plant balloon flower just a tiny bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant balloon flower in San Francisco 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 balloon flower and expect a good harvest is probably September. Any later than that and your balloon flower may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your balloon flower indoors.

Last Frost Date

In San Francisco the average date of last frost happens on January 31. In the coldest months of winter you should expect an average low temperature of 35°F.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for San Francisco and it will vary from year to year. Since half of the time in San Francisco last frost occurs after January 31 be ready to protect your balloon flower in the event of a surprise late frost.

USDA Zone Info for San Francisco

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 Francisco

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