The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of making a decision about when it's possible to plant tree onions is to examine the USDA zone info for Signal Mountain.

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.

Since tree onions do ok in moderate cold you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant tree onions in Signal Mountain 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. If you wait any later than that and 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

In Signal Mountain the average date of last frost happens on April 15. You can expect an average low temperature of 0°F in the coldest months of winter.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Signal Mountain and it changes from year to year. Since half of the time in Signal Mountain you get a frost after April 15 be ready to protect your tree onions if you have one of those late frosts.

USDA Zone Info for Signal Mountain

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Signal Mountain

You may be interested in your other planting guides for Signal Mountain.