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.

In Carbondale you can determine when to plant cosmos by reviewing 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 one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant cosmos in Carbondale 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. You can get started a couple of weeks earlier by starting your cosmos indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Carbondale. In the coldest months of winter you should expect an average low temperature of -5°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Carbondale and it will vary from year to year. Since half of the time in Carbondale last frost occurs after April 15 be ready to cover your cosmos if you have one of those late frosts.

USDA Zone Info for Carbondale

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°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 0°F.

Plants to Grow in Carbondale

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