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.

By reviewing the USDA zone info for Napa it's a good idea to determine when it's a good idea to plant foxglove.

Planting Calendar for Foxglove

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

Since foxglove are one of those plants that can tolerate a little bit of cold weather you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant foxglove 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 foxglove and expect a good harvest is probably October. You probably don't want to wait any later than that or else your foxglove may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your foxglove indoors.

Last Frost Date

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

Since the USDA zone info for Napa is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Napa you get surprised by a frost after February 15 so make sure that you are prepared to cover your foxglove 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.