When to Plant Zinnia in Windsor, CA

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.

It's possible to figure out when it's a good idea to plant zinnia by referring to the USDA zone info for Windsor.


Planting Calendar for Zinnia

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

Zinnia are not cold tolerant which tells us that you really should wait until it warms up after the last frost when the weather gets warmer before you can plant them.

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 Windsor 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. You can get started a few weeks earlier by starting your zinnia indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Windsor. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Windsor is not always accurate the actual date of last frost changes from year to year. Since half of the time in Windsor last frost occurs after February 15 be ready to protect your zinnia in the event of a surprise late frost.

USDA Zone Info for Windsor

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 Low25°F
Highest Expected Low30°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 Windsor

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