The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of estimating when you can plant tree onions is to look at the USDA zone info for Fort Thomas.

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 plants that might not handle the cold.

The earliest that you can plant tree onions in Fort Thomas 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 really do well. You can get started a few weeks earlier by starting your tree onions indoors.

Last Frost Date

The average date of last frost is April 15 in Fort Thomas. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Fort Thomas is an average the actual date of last frost is different every year. Half of the time in Fort Thomas you get surprised by a frost after April 15 so be sure to be ready to cover your tree onions in the event of a late frost.

USDA Zone Info for Fort Thomas

Here is the info for USDA Zone 6b.

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

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

Plants to Grow in Fort Thomas

You may be interested in your other planting guides for Fort Thomas.