One of the first steps you take when you are getting a good idea 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.

You can estimate when it's possible to plant celosia in Napa by referring to the USDA zone info.

Planting Calendar for Celosia

Frost tolerance for celosia:	Not tolerant of frost.
When to plant:	After the last frost.

It's probably a bad idea to plant celosia until after the last frost because they do not do well in cold weather.

The earliest that you can plant celosia in Napa is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant celosia and expect a good harvest is probably September. Any later than that and your celosia may not have a chance to really do well. If you are starting your celosia 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.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Napa and it will vary from year to year. Since half of the time in Napa last frost occurs after February 15 be ready to protect your celosia if you have a late frost.

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.