One of the first steps you take when you are making a decision about your gardening schedule is find your 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.

The earliest that you can plant four o' clock in Tempe can be figured out by looking at the USDA zone info.

Planting Calendar for Four O' Clock

Frost tolerance for four o' clock:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Four O' Clock require warm weather which tells us that you need to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant four o' clock in Tempe 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. You can get started a couple of weeks earlier by starting your four o' clock indoors.

Last Frost Date

The average date of last frost is February 15 in Tempe. It might get as low as 25°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Tempe is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Tempe you get a frost after February 15 be ready to protect your four o' clock in the event of a late frost.

USDA Zone Info for Tempe

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 Tempe

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