One of the best tools that you have as gardeners to help us determine 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 should be looked at to figure out when it's the best time to plant didiscus.

Planting Calendar for Didiscus

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

Since didiscus are barely cold tolerant you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant didiscus 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 didiscus and expect a good harvest is probably September. Any later than that and your didiscus may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your didiscus indoors.

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.

Since the USDA zone info for Napa is not always accurate the actual date of last frost is different every year. Half of the time in Napa it frosts late in the year after February 15 so make sure that you are ready to cover your didiscus 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.