One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of getting a good idea when to plant zinnia is to look at the USDA zone info for Hayward.

Planting Calendar for Zinnia

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

You should not plant zinnia until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant zinnia in Hayward 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 really do well. If you are starting your zinnia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is January 31 in Hayward. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Hayward is an average the actual date of last frost is different every year. Since half of the time in Hayward last frost occurs after January 31 be ready to cover your zinnia in the event of a late frost.

USDA Zone Info for Hayward

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 Low	30°F
Highest Expected Low	35°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 Hayward

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