One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. 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 Suwanee should be reviewed to figure out when it's the best time to plant cosmos.

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 do ok in moderate cold.

The earliest that you can plant cosmos in Suwanee 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. You probably don't want to wait any later than that or else your cosmos may not have a chance to grow to maturity. Starting your cosmos indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Suwanee the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of 5°F.

Keep in mind that USDA zone info for Suwanee is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Suwanee you get a frost after April 15 so just be sure to be ready to cover your cosmos if you have a surprise late frost.

USDA Zone Info for Suwanee

Here is the info for USDA Zone 7b.

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

Plants to Grow in Suwanee

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