One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of figuring out when it's the best time to plant cosmos is to look at the USDA zone info for Sidney.

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

The earliest that you can plant cosmos in Sidney 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

On average the last frost is on April 15 in Sidney. You can expect an average low temperature of -20°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Sidney and it can change quite a bit from year to year. Half of the time in Sidney you get a frost after April 15 so just be sure to be ready to cover your cosmos in the event of a late frost.

USDA Zone Info for Sidney

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 Sidney

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