The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The best time to plant xerianthemum in Napa should be figured out by referring to the USDA zone info.

Planting Calendar for Xerianthemum

Frost tolerance for xerianthemum:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Xerianthemum are one of those plants that can tolerate a tiny bit of cold weather which means that you can start planting them slightly earlier than plants that are more sensitive to the cold.

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

The last month that you can plant xerianthemum and expect a good harvest is probably September. If you wait any later than that and your xerianthemum may not have a chance to fully mature. Starting your xerianthemum 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 USDA zone info for Napa is just an average and the actual date of last frost will vary from year to year. Since half of the time in Napa you get surprised by a frost after February 15 be ready to protect your xerianthemum if you have a surprise 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.