The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when it's a good idea to plant scallions in Costa Mesa by reviewing the USDA zone info.

Planting Calendar for Scallions

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

Scallions do ok in moderate cold which tells us that you can plant them slightly earlier than more sensitive plants.

The earliest that you can plant scallions in Costa Mesa 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 scallions and expect a good harvest is probably September. If you wait any later than that and your scallions may not have a chance to grow to maturity. Starting your scallions indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Costa Mesa the average date of last frost happens on January 31. It might get as low as 35°F during the coldest months of winter.

Keep in mind that USDA zone info for Costa Mesa is just an average and the actual date of last frost changes from year to year. Half of the time in Costa Mesa you get a frost after January 31 so be sure to be ready to protect your scallions if you have one of those late frosts.

USDA Zone Info for Costa Mesa

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in Costa Mesa

You may be interested in your other planting guides for Costa Mesa.