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.

The earliest that you can plant zinnia in Pleasant Hill should be estimated by checking out 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.

You can 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 Pleasant Hill 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 few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Pleasant Hill. You should expect an average low temperature of 25°F in the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Pleasant Hill and it changes from year to year. Half of the time in Pleasant Hill you get surprised by a frost after February 15 so make sure that you are prepared to cover your zinnia if you have one of those late frosts.

USDA Zone Info for Pleasant Hill

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 Pleasant Hill

You may be interested in your other planting guides for Pleasant Hill.