One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant balloon flower in Cupertino can be estimated by looking at the USDA zone info.

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 a bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant balloon flower in Cupertino 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. You probably don't want to wait any later than that or else your balloon flower may not have a chance to really do well. You can get started a few weeks earlier by starting your balloon flower indoors.

Last Frost Date

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

Always keep in mind that USDA zone info for Cupertino is just an average and the actual date of last frost changes from year to year. Half of the time in Cupertino last frost occurs after February 15 so always be ready to cover your balloon flower in the event of one of those late frosts.

USDA Zone Info for Cupertino

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 Cupertino

You may be interested in your other planting guides for Cupertino.