Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can determine when to plant sweet williams in Zone 9a by reviewing the USDA zone info.

Planting Calendar for Sweet Williams

Frost tolerance for sweet williams:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Sweet Williams do well in moderate cold which tells us that you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant sweet williams in Zone 9a is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant sweet williams and expect a good harvest is probably October. You probably don't want to wait any later than that or else your sweet williams may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your sweet williams indoors.

Last Frost Date

The average date of last frost is February 15 in Zone 9a. You can expect an average low temperature of 20°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Zone 9a is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Zone 9a there is a last frost after February 15 be ready to protect your sweet williams if you have a late frost.

USDA Zone Info for Zone 9a

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Zone 9a

You may be interested in your other planting guides for Zone 9a.