One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of figuring out when it's a good idea to plant broccoli is to consult the USDA zone info for Napa.

Planting Calendar for Broccoli

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

Broccoli are moderately cold tolerant which tells us that you can start planting them earlier than other plants that might not handle the cold.

The earliest that you can plant broccoli 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 broccoli and expect a good harvest is probably October. If you wait any later than that and your broccoli may not have a chance to fully mature. Starting your broccoli indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Napa the average date of last frost happens on February 15. You should expect an average low temperature of 25°F in the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Napa and it can change quite a bit from year to year. Since half of the time in Napa it frosts late in the year after February 15 be ready to cover your broccoli in the event of 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.