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 Huntsville should be read to figure out when it's a good idea 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 are not cold tolerant it's 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 Huntsville 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. You can get started a few weeks earlier by starting your four-o-clock flower indoors.

Last Frost Date

In Huntsville the average date of last frost happens on March 15. In the coldest months of winter you can expect an average low temperature of 15°F.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Huntsville and it will vary from year to year. Since half of the time in Huntsville it frosts late in the year after March 15 be ready to protect your four-o-clock flower in the event of a late frost.

USDA Zone Info for Huntsville

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Huntsville

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