Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Marion you can estimate when to plant helianthemum by referring to the USDA zone info.

Planting Calendar for Helianthemum

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

Since helianthemum are moderately cold tolerant you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant helianthemum in Marion 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. You probably don't want to wait any later than that or else your helianthemum may not have a chance to really do well. You can get started a little bit earlier by starting your helianthemum indoors.

Last Frost Date

In Marion the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 5°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Marion and it can change quite a bit from year to year. Half of the time in Marion last frost occurs after April 15 so make sure that you are prepared to protect your helianthemum if you have a late frost.

USDA Zone Info for Marion

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Marion

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