One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to determine when it's possible to plant sweet williams by reviewing the USDA zone info for Sunnyvale.

Planting Calendar for Sweet Williams

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

You can plant sweet williams a little bit earlier in the year because they do well in moderate cold.

The earliest that you can plant sweet williams in Sunnyvale 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 williams and expect a good harvest is probably September. If you wait any later than that and your sweet williams may not have a chance to fully mature. Starting your sweet williams 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 March 15 in Sunnyvale. It might get as low as 10°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Sunnyvale is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Sunnyvale you get surprised by a frost after March 15 be ready to protect your sweet williams in the event of one of those late frosts.

USDA Zone Info for Sunnyvale

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Sunnyvale

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