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.

A common way of determining when to plant zinnia is to look at the USDA zone info for American Canyon.

Planting Calendar for Zinnia

Frost tolerance for zinnia:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since zinnia do not do well in cold weather you need to wait until after the last frost before you can plant them.

The earliest that you can plant zinnia in American Canyon 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. If you wait any later than that and your zinnia may not have a chance to fully mature. 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

In American Canyon the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

It's important to remember that USDA zone info for American Canyon is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in American Canyon there is a last frost after February 15 be ready to cover your zinnia in the event of one of those late frosts.

USDA Zone Info for American Canyon

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 American Canyon

You may be interested in your other planting guides for American Canyon.