One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of figuring out when it's the best time to plant cosmos is to examine the USDA zone info for Bloomington.

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 do ok in very little cold which tells us that you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant cosmos in Bloomington 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 really do well. You can get started a little bit earlier by starting your cosmos indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Bloomington. In the coldest months of winter you should expect an average low temperature of -10°F.

Always keep in mind that USDA zone info for Bloomington may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Bloomington there is a last frost after April 15 be ready to protect your cosmos in the event of one of those late frosts.

USDA Zone Info for Bloomington

Here is the info for USDA Zone 6a.

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

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Bloomington

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