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.

A way of making a decision about when it's possible to plant sweet sultan is to refer to the USDA zone info for Napa.

Planting Calendar for Sweet Sultan

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

Sweet Sultan are barely cold tolerant which means that you can plant them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant sweet sultan 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 sweet sultan and expect a good harvest is probably September. You probably don't want to wait any later than that or else your sweet sultan may not have a chance to grow to maturity. Starting your sweet sultan indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Always keep in mind that USDA zone info for Napa is not always accurate and the actual date of last frost is different every year. Since half of the time in Napa last frost occurs after February 15 be ready to protect your sweet sultan in the event of a 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.