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.

By referring to the USDA zone info for Stewartville you should be able to estimate when it's possible to plant erysimum.

Planting Calendar for Erysimum

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

Erysimum do well in moderate cold which tells us that you can start planting them earlier than other plants that might not handle the cold.

The earliest that you can plant erysimum in Stewartville 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 erysimum and expect a good harvest is probably August. If you wait any later than that and your erysimum may not have a chance to fully mature. If you are starting your erysimum indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Stewartville the average date of last frost happens on May 15. You should expect an average low temperature of -25°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Stewartville and it is different every year. Half of the time in Stewartville last frost occurs after May 15 so make sure that you are ready to cover your erysimum in the event of a surprise late frost.

USDA Zone Info for Stewartville

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 Stewartville

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