One of the best tools that you have as gardeners to help us figure out 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.

One way of estimating when it's the best time to plant gomphrena is to examine the USDA zone info for Corona.

Planting Calendar for Gomphrena

Frost tolerance for gomphrena:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant gomphrena a bit earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant gomphrena in Corona 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 gomphrena and expect a good harvest is probably September. If you wait any later than that and your gomphrena may not have a chance to fully mature. If you are starting your gomphrena indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Remember that USDA zone info for Corona is just an average and the actual date of last frost is different every year. Half of the time in Corona it frosts late in the year after February 15 so make sure that you are prepared to cover your gomphrena in the event of one of those late frosts.

USDA Zone Info for Corona

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 Corona

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