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.

You will be able to estimate when it's the best time to plant four-o-clock flower by looking at the USDA zone info for Harlan.

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.

It's not a good idea to plant four-o-clock flower until after all chance of frost has passed because they require warm weather.

The earliest that you can plant four-o-clock flower in Harlan 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

On average all chance of frost has passed is on April 15 in Harlan. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Harlan is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in Harlan you get a frost after April 15 be ready to cover your four-o-clock flower if you have a late frost.

USDA Zone Info for Harlan

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

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

Plants to Grow in Harlan

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