One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Sedona should be used to estimate when it's a good idea 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.

Since cosmos do ok in moderate cold you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant cosmos in Sedona 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. You probably don't want to wait any later than that or else your cosmos may not have a chance to fully mature. Starting your cosmos indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Sedona the average date of last frost happens on March 15. You should expect an average low temperature of 15°F in the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Sedona and it will vary from year to year. Half of the time in Sedona you get surprised by a frost after March 15 so always be ready to cover your cosmos if you have a surprise late frost.

USDA Zone Info for Sedona

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

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

Plants to Grow in Sedona

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