Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Petersburg you can determine when it's possible to plant gomphrena by referring to the USDA zone info.

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 do ok in moderate cold which tells us that you can get them planted just a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant gomphrena in Petersburg 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 gomphrena and expect a good harvest is probably August. You probably don't want to wait any later than that or else your gomphrena may not have a chance to fully mature. Starting your gomphrena indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Petersburg the average date of last frost happens on April 15. You can expect an average low temperature of 5°F in the coldest months of winter.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Petersburg and it will vary from year to year. Half of the time in Petersburg last frost occurs after April 15 so be sure to be ready to cover your gomphrena if you have a surprise late frost.

USDA Zone Info for Petersburg

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Petersburg

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