Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Ogden can be read to estimate when to plant cosmos.

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 tend to make it in mild cold which means that you can plant them slightly earlier in the year than other plants that might not handle the cold.

The earliest that you can plant cosmos in Ogden 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. Starting your cosmos indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Ogden. In the coldest months of winter you should expect an average low temperature of 0°F.

It's important to remember that USDA zone info for Ogden is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Ogden you get surprised by a frost after April 15 so be sure to be ready to cover your cosmos if you have one of those late frosts.

USDA Zone Info for Ogden

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Ogden

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