When to Plant Zinnia in Hartsville, SC

One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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 first opportunity to plant zinnia in Hartsville can be estimated by checking out the USDA zone info.


Planting Calendar for Zinnia

Frost tolerance for zinnia: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

You can not plant zinnia until after the last frost when the weather gets warmer because they are not cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant zinnia
Possibly ok, but a risky time to plant zinnia
Probably not a good time to plant zinnia

The earliest that you can plant zinnia in Hartsville 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 zinnia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your zinnia may not have a chance to fully mature. If you are starting your zinnia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Hartsville. In the coldest months of winter you can expect an average low temperature of 10°F.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Hartsville and it can change quite a bit from year to year. Half of the time in Hartsville you get surprised by a frost after March 15 so be sure to be ready to cover your zinnia if you have a late frost.

USDA Zone Info for Hartsville

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 Low10°F
Highest Expected Low15°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 Hartsville

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