One of the first steps you take when you are getting a good idea 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 USDA zone info for Holly can be reffered to in order to determine when it's the best time to plant four o' clock.

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.

Since four o' clock require warm weather you really should wait until after the last frost has passed before you can plant them.

The earliest that you can plant four o' clock in Holly 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 and expect a good harvest is probably August. If you wait any later than that and your four o' clock may not have a chance to fully mature. You can get started a little bit earlier by starting your four o' clock indoors.

Last Frost Date

On average the last frost is on April 15 in Holly. In the coldest months of winter you can expect an average low temperature of -10°F.

Just be sure to remember that USDA zone info for Holly is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Holly last frost occurs after April 15 be ready to cover your four o' clock if you have a late frost.

USDA Zone Info for Holly

Here is the info for USDA Zone 6a.

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

Plants to Grow in Holly

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