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.

In Salt Lake City you can determine when to plant four-o-clock flower by referring to the USDA zone info.

Planting Calendar for Four-o-clock flower

Frost tolerance for four-o-clock flower:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since four-o-clock flower require warm weather it is necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant four-o-clock flower in Salt Lake City is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant four-o-clock flower and expect a good harvest is probably August. You probably don't want to wait any later than that or else your four-o-clock flower may not have a chance to grow to maturity. If you are starting your four-o-clock flower indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Salt Lake City. In the coldest months of winter you should expect an average low temperature of 5°F.

Since the USDA zone info for Salt Lake City is not always accurate the actual date of last frost is different every year. Half of the time in Salt Lake City last frost occurs after April 15 so just be sure to be ready to cover your four-o-clock flower if you have a late frost.

USDA Zone Info for Salt Lake City

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Salt Lake City

You may be interested in your other planting guides for Salt Lake City.