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

It's a good idea to figure out when it's a good idea to plant cosmos by referring to the USDA zone info for Pontiac.

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 barely cold tolerant you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant cosmos in Pontiac 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 grow to maturity. Starting your cosmos indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Pontiac. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Pontiac is an average the actual date of last frost will vary from year to year. Half of the time in Pontiac it frosts late in the year after April 15 so make sure that you are ready to protect your cosmos if you have a surprise late frost.

USDA Zone Info for Pontiac

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Pontiac

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