Before planting it is a good idea to find your USDA Zone info to figure out 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 Scottsdale should be used to estimate when it's a good idea to plant flower-of-an-hour.

Planting Calendar for Flower-of-an-Hour

Frost tolerance for flower-of-an-hour:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Flower-of-an-Hour are one of those plants that can tolerate a tiny bit of cold weather which means that you can start planting them slightly earlier than other frost tender plants.

The earliest that you can plant flower-of-an-hour in Scottsdale is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant flower-of-an-hour and expect a good harvest is probably September. Any later than that and your flower-of-an-hour may not have a chance to really do well. If you are starting your flower-of-an-hour indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Scottsdale the average date of last frost happens on February 15. You should expect an average low temperature of 25°F in the coldest months of winter.

Always keep in mind that USDA zone info for Scottsdale may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Scottsdale you get a frost after February 15 be ready to cover your flower-of-an-hour in the event of one of those late frosts.

USDA Zone Info for Scottsdale

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Scottsdale

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