Before planting it is a good idea to find your USDA Zone info to estimate 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.

The USDA zone info for Zone 8a can be used to estimate when you can 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 are barely cold tolerant which means that you can plant them slightly earlier than more sensitive plants.

The earliest that you can plant tree onions in Zone 8a 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

In Zone 8a the average date of last frost happens on March 15. You can expect an average low temperature of 10°F in the coldest months of winter.

It's important to remember that USDA zone info for Zone 8a may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Zone 8a you get surprised by a frost after March 15 be ready to protect your tree onions if you have a late frost.

USDA Zone Info for Zone 8a

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Zone 8a

You may be interested in your other planting guides for Zone 8a.