One of the best tools that you have as gardeners to help us determine 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.

A way of determining when to plant four o' clock is to examine the USDA zone info for Scottsdale.

Planting Calendar for Four O' Clock

Frost tolerance for four o' clock:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You really shouldn't plant four o' clock until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant four o' clock in Scottsdale 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 four o' clock and expect a good harvest is probably September. You probably don't want to wait any later than that or else your four o' clock may not have a chance to fully mature. If you are starting your four o' clock indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in Scottsdale. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Scottsdale is not always accurate the actual date of last frost is different every year. Since half of the time in Scottsdale it frosts late in the year after February 15 be ready to cover your four o' clock if you have 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.