The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant onions in Sunnyvale can be determined by using the USDA zone info.

Planting Calendar for Onions

Frost tolerance for onions:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Onions are one of those plants that can tolerate quite a bit of cold weather which tells us that you can get them planted much earlier than plants that are more sensitive to the cold.

The earliest that you can plant onions in Sunnyvale 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 onions and expect a good harvest is probably October. Any later than that and your onions may not have a chance to grow to maturity. Starting your onions 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 Sunnyvale. You can expect an average low temperature of 25°F in the coldest months of winter.

Keep in mind that USDA zone info for Sunnyvale is an average and the actual date of last frost changes from year to year. Half of the time in Sunnyvale you get a frost after February 15 so just be sure to be ready to protect your onions if you have one of those late frosts.

USDA Zone Info for Sunnyvale

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 Sunnyvale

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