Before planting it is a good idea to find your USDA Zone info to figure out 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.

You should be able to figure out when you can plant tree onions by checking out the USDA zone info for El Cerrito.

Planting Calendar for Tree onions

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

Tree onions do ok in moderate cold which tells us that you can plant them slightly earlier than other frost tender plants.

The earliest that you can plant tree onions in El Cerrito 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 tree onions and expect a good harvest is probably September. If you wait any later than that and your tree onions may not have a chance to fully mature. You can get started a little bit earlier by starting your tree onions indoors.

Last Frost Date

The average date of last frost is January 31 in El Cerrito. You should expect an average low temperature of 30°F in the coldest months of winter.

Remember that USDA zone info for El Cerrito is an average and the actual date of last frost will vary from year to year. Half of the time in El Cerrito you get surprised by a frost after January 31 so make sure that you are prepared to protect your tree onions if you have a late frost.

USDA Zone Info for El Cerrito

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 El Cerrito

You may be interested in your other planting guides for El Cerrito.