Before planting it is a good idea to find your USDA Zone info to estimate 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.

The first opportunity to plant sweet williams in Sonora can be figured out by referring to 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 a little bit of cold which means that you can plant them a little bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant sweet williams in Sonora 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. Any later than that and your sweet williams may not have a chance to really do well. If you are starting your sweet williams indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Sonora the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 20°F.

Keep in mind that USDA zone info for Sonora 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 Sonora last frost occurs after February 15 be ready to cover your sweet williams in the event of one of those late frosts.

USDA Zone Info for Sonora

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 Sonora

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