One of the first steps you take when you are making a decision about your gardening schedule is find your 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 best time to plant marigold in Sonora should be estimated by reviewing the USDA zone info.

Planting Calendar for Marigold

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

It's not a good idea to plant marigold until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant marigold in Sonora 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. You probably don't want to wait any later than that or else your marigold may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your marigold indoors.

Last Frost Date

The average date of last frost is February 15 in Sonora. You can expect an average low temperature of 20°F in the coldest months of winter.

It's important to remember that USDA zone info for Sonora is an average and the actual date of last frost will vary from year to year. Half of the time in Sonora you get a frost after February 15 so just be sure to be ready to protect your marigold in the event of one of those late frosts.

USDA Zone Info for Sonora

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Sonora

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