Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant cosmos in Westerville can be figured out by using the USDA zone info.

Planting Calendar for Cosmos

Frost tolerance for cosmos:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant cosmos slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant cosmos in Westerville 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 cosmos and expect a good harvest is probably August. Any later than that and your cosmos may not have a chance to really do well. Starting your cosmos indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Westerville the average date of last frost happens on April 15. You should expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Westerville is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Westerville you get a frost after April 15 so make sure that you are ready to protect your cosmos if you have a late frost.

USDA Zone Info for Westerville

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 Westerville

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