One of the first steps you take when you are determining your gardening schedule is find your 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.

By reviewing the USDA zone info for Riverside you should be able to estimate when you can plant sweet sultan.

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.

Since sweet sultan do ok in moderate cold you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant sweet sultan in Riverside 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

The average date of last frost is February 15 in Riverside. You should expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Riverside is an average the actual date of last frost will vary from year to year. Since half of the time in Riverside it frosts late in the year after February 15 be ready to cover your sweet sultan if you have a late frost.

USDA Zone Info for Riverside

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 Riverside

You may be interested in your other planting guides for Riverside.