Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of estimating when it's possible to plant gomphrena is to check out the USDA zone info for Millbrae.

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 can survive in some cold which means that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant gomphrena in Millbrae 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 few weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Millbrae. In the coldest months of winter you should expect an average low temperature of 30°F.

Just be sure to remember that USDA zone info for Millbrae is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Millbrae there is a last frost after January 31 so always be ready to cover your gomphrena in the event of a surprise late frost.

USDA Zone Info for Millbrae

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Millbrae

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