The USDA Zone info is a great tool for gardeners to help us estimate 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.

By checking out the USDA zone info for Napa it's possible to figure out when to plant steirodiscus.

Planting Calendar for Steirodiscus

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

Steirodiscus are one of those plants that can tolerate a tiny bit of cold weather which tells us that you can get them planted just a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant steirodiscus 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 steirodiscus and expect a good harvest is probably September. You probably don't want to wait any later than that or else your steirodiscus may not have a chance to really do well. Starting your steirodiscus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer 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 changes from year to year. Since half of the time in Napa last frost occurs after February 15 be ready to protect your steirodiscus 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.