Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. 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 flowering kale in Napa should be determined by using the USDA zone info.

Planting Calendar for Flowering Kale

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

Since flowering kale do well in moderate cold you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant flowering kale in Napa 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 flowering kale and expect a good harvest is probably October. Any later than that and your flowering kale may not have a chance to grow to maturity. If you are starting your flowering kale indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Napa. You can expect an average low temperature of 25°F in the coldest months of winter.

Keep in mind that USDA zone info for Napa is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Napa last frost occurs after February 15 so make sure that you are prepared to cover your flowering kale if you have one of those late frosts.

USDA Zone Info for Napa

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 Napa

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