One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of getting a good idea when it's possible to plant tree onions is to examine the USDA zone info for Savannah.

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 means that you can start planting them slightly earlier than other frost tender plants.

The earliest that you can plant tree onions in Savannah 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 couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Savannah. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Savannah is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in Savannah there is a last frost after April 15 be ready to protect your tree onions if you have a surprise late frost.

USDA Zone Info for Savannah

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Savannah

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