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.

One way of getting a good idea when it's the best time to plant helianthemum is to consult the USDA zone info for Clarkston.

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 plant them earlier than more sensitive plants.

The earliest that you can plant helianthemum in Clarkston 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

The average date of last frost is April 15 in Clarkston. It might get as low as 5°F during the coldest months of winter.

Remember that USDA zone info for Clarkston may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Clarkston it frosts late in the year after April 15 so make sure that you are prepared to protect your helianthemum in the event of a surprise late frost.

USDA Zone Info for Clarkston

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 Clarkston

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