One of the first steps you take when you are making a decision about your gardening schedule is find your 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.

A common way of estimating when to plant helianthemum is to refer to the USDA zone info for Marion.

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 one of those plants that can tolerate a little bit of cold weather 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. 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

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 -10°F.

Always keep in mind that USDA zone info for Marion is an average and the actual date of last frost is different every year. Since half of the time in Marion you get a frost after April 15 be ready to cover your helianthemum if you have a late frost.

USDA Zone Info for Marion

Here is the info for USDA Zone 6a.

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

Plants to Grow in Marion

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