The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Ishpeming can be read to determine 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 well in moderate cold which means that you can start planting them earlier than plants that are more sensitive to the cold.

The earliest that you can plant helianthemum in Ishpeming 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. Any later than that and your helianthemum may not have a chance to grow to maturity. You can get started a little bit earlier by starting your helianthemum indoors.

Last Frost Date

The average date of last frost is May 15 in Ishpeming. It might get as low as -25°F during the coldest months of winter.

Remember that USDA zone info for Ishpeming is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Ishpeming last frost occurs after May 15 be ready to cover your helianthemum in the event of a late frost.

USDA Zone Info for Ishpeming

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 Ishpeming

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