One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Centerville you should be able to figure out when it's possible to plant helianthemum.

Planting Calendar for Helianthemum

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

Helianthemum do ok in some cold which tells us that you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant helianthemum in Centerville 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 fully mature. If you are starting your helianthemum indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on March 15 in Centerville. In the coldest months of winter you can expect an average low temperature of 10°F.

Keep in mind 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 Centerville and it can change quite a bit from year to year. Since half of the time in Centerville last frost occurs after March 15 be ready to cover your helianthemum in the event of one of those late frosts.

USDA Zone Info for Centerville

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 Low	10°F
Highest Expected Low	15°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 Centerville

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