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.

You should be able to determine when you can plant cosmos by looking at the USDA zone info for Reedsburg.

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 are barely cold tolerant which means that you can start planting them slightly earlier than more sensitive plants.

The earliest that you can plant cosmos in Reedsburg 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. If you are starting your cosmos indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Reedsburg. You should expect an average low temperature of -20°F in the coldest months of winter.

Remember that USDA zone info for Reedsburg is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Reedsburg it frosts late in the year after April 15 be ready to protect your cosmos in the event of one of those late frosts.

USDA Zone Info for Reedsburg

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Reedsburg

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