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

In Zone 7b you can figure out when it's a good idea to plant cosmos by referring to 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.

Since cosmos are one of those plants that can tolerate a tiny bit of cold weather you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant cosmos in Zone 7b 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 grow to maturity. You can get started a couple of weeks earlier by starting your cosmos indoors.

Last Frost Date

In Zone 7b the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 5°F.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Zone 7b and it is different every year. Half of the time in Zone 7b there is a last frost after April 15 so make sure that you are prepared to cover your cosmos if you have a surprise late frost.

USDA Zone Info for Zone 7b

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 Zone 7b

You may be interested in your other planting guides for Zone 7b.