Before planting it is a good idea to find your USDA Zone info to estimate 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 figuring out when it's possible to plant erysimum is to use the USDA zone info for Colby.

Planting Calendar for Erysimum

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

You can plant erysimum a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant erysimum in Colby 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 erysimum and expect a good harvest is probably September. If you wait any later than that and your erysimum may not have a chance to fully mature. You can get started a little bit earlier by starting your erysimum indoors.

Last Frost Date

The average date of last frost is April 15 in Colby. You can expect an average low temperature of -15°F in the coldest months of winter.

Remember that USDA zone info for Colby is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Colby last frost occurs after April 15 be ready to cover your erysimum if you have a late frost.

USDA Zone Info for Colby

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Colby

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