One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of making a decision about when to plant onions is to consult the USDA zone info for Circleville.

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 earlier in the year than other plants that might not handle the cold.

The earliest that you can plant onions in Circleville 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. You probably don't want to wait any later than that or else your onions may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your onions indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Circleville. You can expect an average low temperature of -10°F in the coldest months of winter.

Always keep in mind that USDA zone info for Circleville may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Circleville you get a frost after April 15 be ready to cover your onions if you have a late frost.

USDA Zone Info for Circleville

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 Circleville

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