One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Grass Valley can be used to determine when it's the best time to plant gomphrena.

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.

Gomphrena are barely cold tolerant which means that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant gomphrena in Grass Valley 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. You probably don't want to wait any later than that or else your gomphrena may not have a chance to really do well. If you are starting your gomphrena indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Grass Valley the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 20°F.

Since the USDA zone info for Grass Valley is just an average the actual date of last frost is different every year. Half of the time in Grass Valley there is a last frost after February 15 so just be sure to be ready to protect your gomphrena in the event of a surprise late frost.

USDA Zone Info for Grass Valley

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 Grass Valley

You may be interested in your other planting guides for Grass Valley.