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

By checking out the USDA zone info for Signal Mountain you should be able to estimate when it's the best time to plant onions.

Planting Calendar for Onions

Frost tolerance for onions:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since onions are one of those plants that can tolerate quite a bit of cold weather you can plant them a lot earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant onions in Signal Mountain is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant onions and expect a good harvest is probably September. Any later than that and your onions may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your onions indoors.

Last Frost Date

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

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Signal Mountain and it will vary from year to year. Since half of the time in Signal Mountain you get surprised by a frost after April 15 be ready to protect your onions if you have a late frost.

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.