The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Vallejo should be looked at to determine when it's the best time to plant zinnia.

Planting Calendar for Zinnia

Frost tolerance for zinnia:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

You can not plant zinnia until after the last frost because they are not cold tolerant.

The earliest that you can plant zinnia in Vallejo is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant zinnia and expect a good harvest is probably September. You probably don't want to wait any later than that or else your zinnia may not have a chance to really do well. If you are starting your zinnia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Vallejo. You should expect an average low temperature of 25°F in the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Vallejo and it changes from year to year. Half of the time in Vallejo you get a frost after February 15 so make sure that you are ready to protect your zinnia in the event of a surprise late frost.

USDA Zone Info for Vallejo

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 Vallejo

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