Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. 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 estimate when it's a good idea to plant cosmos by using the USDA zone info for Spirit Lake.

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 a bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant cosmos in Spirit Lake 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 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

In Spirit Lake the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Spirit Lake and it can change quite a bit from year to year. Since half of the time in Spirit Lake last frost occurs after April 15 be ready to cover your cosmos in the event of one of those late frosts.

USDA Zone Info for Spirit Lake

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 Spirit Lake

You may be interested in your other planting guides for Spirit Lake.