One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Napa can be reviewed to estimate when you can plant anchusa.

Planting Calendar for Anchusa

Frost tolerance for anchusa:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Anchusa do well in cold which means that you can plant them much earlier than other frost tender plants.

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

Last Frost Date

The average date of last frost is February 15 in Napa. It might get as low as 25°F during the coldest months of winter.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Napa and it 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 ready to cover your anchusa 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.