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.

By reviewing the USDA zone info for Auburn you will be able to estimate when it's the best time to plant tree onions.

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 means 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 March. However, you really should wait until April 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 August. 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 little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Auburn. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Auburn may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Auburn you get a frost after April 15 be ready to cover your tree onions if you have a surprise late frost.

USDA Zone Info for Auburn

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Auburn

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