Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant tree onions in North Charleston should be figured out by reviewing the USDA zone info.

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 a bit earlier in the year than other frost tender plants.

The earliest that you can plant tree onions in North Charleston 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. You can get started a few weeks earlier by starting your tree onions indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in North Charleston. You should expect an average low temperature of 15°F in the coldest months of winter.

Keep in mind that USDA zone info for North Charleston is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in North Charleston you get surprised by a frost after March 15 so just be sure to be ready to protect your tree onions if you have a surprise late frost.

USDA Zone Info for North Charleston

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in North Charleston

You may be interested in your other planting guides for North Charleston.