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.

The best time to plant onions in San Juan Capistrano should be determined by looking at the USDA zone info.

Planting Calendar for Onions

Frost tolerance for onions:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Onions do well in cold weather which means that you can plant them quite a bit earlier in the year than more sensitive plants.

The earliest that you can plant onions in San Juan Capistrano is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant onions and expect a good harvest is probably October. If you wait any later than that and your onions may not have a chance to fully mature. If you are starting your onions indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on January 31 in San Juan Capistrano. In the coldest months of winter you should expect an average low temperature of 30°F.

Remember that USDA zone info for San Juan Capistrano is just an average and the actual date of last frost will vary from year to year. Half of the time in San Juan Capistrano it frosts late in the year after January 31 so make sure that you are prepared to protect your onions if you have a surprise late frost.

USDA Zone Info for San Juan Capistrano

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 San Juan Capistrano

You may be interested in your other planting guides for San Juan Capistrano.