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.

By checking out the USDA zone info for Jackson you should be able to figure out when it's a good idea 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 are moderately cold tolerant which means that you can start planting them earlier than other frost tender plants.

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

The last month that you can plant helianthemum and expect a good harvest is probably August. If you wait any later than that and your helianthemum may not have a chance to grow to maturity. Starting your helianthemum indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost is on May 15 in Jackson. In the coldest months of winter you can expect an average low temperature of -25°F.

Since the USDA zone info for Jackson is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Jackson it frosts late in the year after May 15 so just be sure to be ready to cover your helianthemum if you have a late frost.

USDA Zone Info for Jackson

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Jackson

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