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

The first opportunity to plant tree onions in Zone 11a should be determined by checking out the USDA zone info.

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.

Since tree onions are barely cold tolerant you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant tree onions in Zone 11a 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 tree onions and expect a good harvest is probably November. You probably don't want to wait any later than that or else your tree onions may not have a chance to really do well. Starting your tree onions indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Zone 11a it never frosts. In the coldest months of winter you should expect an average low temperature of 40°F.

Keep in mind that USDA zone info for Zone 11a is not always accurate and the actual date of last frost can change quite a bit from year to year. Since it never frosts in Zone 11a you do not have to be ready to protect your tree onions if you have a late frost.

USDA Zone Info for Zone 11a

Here is the info for USDA Zone 11a.

Average Date of Last Frost (spring)	Never
Average Date of First Frost (fall)	Never
Lowest Expected Low	40°F
Highest Expected Low	45°F

This means that on a really cold year, the coldest it will get is 40°F. On most years you should be prepared to experience lows near 45°F.

Plants to Grow in Zone 11a

You may be interested in your other planting guides for Zone 11a.