Before planting it is a good idea to find your USDA Zone info to determine 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.

A common way of determining when it's a good idea to plant helianthemum is to consult the USDA zone info for Detroit Lakes.

Planting Calendar for Helianthemum

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

Helianthemum can survive in mild cold which means that you can plant them a little earlier in the year than other plants that might not handle the cold.

The earliest that you can plant helianthemum in Detroit Lakes 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. You can get started a little bit earlier by starting your helianthemum indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Detroit Lakes. It might get as low as -35°F during the coldest months of winter.

Remember that USDA zone info for Detroit Lakes may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Detroit Lakes last frost occurs after May 15 be ready to cover your helianthemum if you have a late frost.

USDA Zone Info for Detroit Lakes

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-35°F
Highest Expected Low	-30°F

This means that on a really cold year, the coldest it will get is -35°F. On most years you should be prepared to experience lows near -30°F.

Plants to Grow in Detroit Lakes

You may be interested in your other planting guides for Detroit Lakes.