Before planting it is a good idea to find your USDA Zone info to determine 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 Richland should be used to determine when to plant four-o-clock flower.

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 do not do well in cold weather it is necessary to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant four-o-clock flower in Richland 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 fully mature. You can get started a little bit earlier by starting your four-o-clock flower indoors.

Last Frost Date

In Richland the average date of last frost happens on March 15. You should expect an average low temperature of 10°F in the coldest months of winter.

Keep in mind that USDA zone info for Richland is an average and the actual date of last frost will vary from year to year. Half of the time in Richland you get surprised by a frost after March 15 so make sure that you are ready to cover your four-o-clock flower in the event of a surprise late frost.

USDA Zone Info for Richland

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Richland

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