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 Dearborn you can figure out when to plant cosmos 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.

Cosmos tend to make it in some cold which means that you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant cosmos in Dearborn 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. If you wait any later than that and your cosmos may not have a chance to fully mature. You can get started a few weeks earlier by starting your cosmos indoors.

Last Frost Date

In Dearborn the average date of last frost happens on April 15. It might get as low as -5°F during the coldest months of winter.

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

USDA Zone Info for Dearborn

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 Dearborn

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