Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of figuring out when it's a good idea to plant helianthemum is to refer to the USDA zone info for Clarksville.

Planting Calendar for Helianthemum

Frost tolerance for helianthemum:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant helianthemum a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant helianthemum in Clarksville is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant helianthemum and expect a good harvest is probably September. If you wait any later than that and your helianthemum may not have a chance to really do well. If you are starting your helianthemum indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Clarksville the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of 0°F.

Remember that USDA zone info for Clarksville is not always accurate and the actual date of last frost is different every year. Since half of the time in Clarksville you get surprised by a frost after April 15 be ready to cover your helianthemum in the event of a late frost.

USDA Zone Info for Clarksville

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Clarksville

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