One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to figure out when you can plant tree onions by reviewing the USDA zone info for Auburn.

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 very little cold which tells us that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant tree onions in Auburn 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. You probably don't want to wait any later than that or else your tree onions may not have a chance to fully mature. Starting your tree onions indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Auburn. In the coldest months of winter you should expect an average low temperature of 25°F.

Since the USDA zone info for Auburn is not always accurate the actual date of last frost changes from year to year. Since half of the time in Auburn last frost occurs after February 15 be ready to protect your tree onions in the event of a late frost.

USDA Zone Info for Auburn

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Auburn

You may be interested in your other planting guides for Auburn.