One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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 marigold in Healdsburg can be estimated by using the USDA zone info.

Planting Calendar for Marigold

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

It's probably not a good idea to plant marigold until after the last frost because they are not cold tolerant.

The earliest that you can plant marigold 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 marigold and expect a good harvest is probably September. Any later than that and your marigold may not have a chance to really do well. Starting your marigold indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Healdsburg. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Healdsburg is not always accurate the actual date of last frost will vary from year to year. Half of the time in Healdsburg there is a last frost after February 15 so make sure that you are prepared to cover your marigold if you have 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.