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.

The USDA zone info for Shelbyville should be reffered to in order to estimate when it's a good idea to 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 do ok in moderate cold which tells us that you can plant them slightly earlier than more sensitive plants.

The earliest that you can plant tree onions in Shelbyville 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. You probably don't want to wait any later than that or else your tree onions may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your tree onions indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Shelbyville. You should expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Shelbyville is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Shelbyville you get surprised by a frost after April 15 be ready to protect your tree onions in the event of a late frost.

USDA Zone Info for Shelbyville

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°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 -5°F.

Plants to Grow in Shelbyville

You may be interested in your other planting guides for Shelbyville.