One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant zinnia in Healdsburg 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 all chance of frost has passed.

Since zinnia require warm weather it is necessary to wait until after the last frost before you can plant them.

The earliest that you can plant zinnia in Healdsburg 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. 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 little bit earlier.

Last Frost Date

In Healdsburg the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 25°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Healdsburg and it can change quite a bit from year to year. Half of the time in Healdsburg last frost occurs after February 15 so be sure to be ready to cover your zinnia in the event of a late frost.

USDA Zone Info for Healdsburg

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 Healdsburg

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