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.

It's possible to figure out when it's a good idea to plant tree onions by looking at the USDA zone info for Zone 11b.

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 one of those plants that can tolerate a tiny bit of cold weather you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant tree onions in Zone 11b 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. Any later than that and your tree onions may not have a chance to grow to maturity. If you are starting your tree onions indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Zone 11b it never frosts. It might get as low as 45°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Zone 11b 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 11b you do not have to be ready to cover your tree onions in the event of one of those late frosts.

USDA Zone Info for Zone 11b

Here is the info for USDA Zone 11b.

Average Date of Last Frost (spring)	Never
Average Date of First Frost (fall)	Never
Lowest Expected Low	45°F
Highest Expected Low	50°F

This means that on a really cold year, the coldest it will get is 45°F. On most years you should be prepared to experience lows near 50°F.

Plants to Grow in Zone 11b

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