When to Plant Zinnia in Piedmont, CA

One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant zinnia in Piedmont can be figured out by looking at the USDA zone info.


Planting Calendar for Zinnia

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

It's probably a bad idea to plant zinnia until after the last frost has passed because they are not cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant zinnia
Possibly ok, but a risky time to plant zinnia
Probably not a good time to plant zinnia

The earliest that you can plant zinnia in Piedmont 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 zinnia and expect a good harvest is probably September. Any later than that and your zinnia may not have a chance to fully mature. Starting your zinnia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Piedmont the average date of last frost happens on January 31. It might get as low as 30°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Piedmont is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Piedmont there is a last frost after January 31 so be sure to be ready to cover your zinnia if you have one of those late frosts.

USDA Zone Info for Piedmont

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)January 31
Average Date of First Frost (fall)December 15
Lowest Expected Low30°F
Highest Expected Low35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Piedmont

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