When to Plant Erysimum in Zone 4b

One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant erysimum in Zone 4b should be determined by reviewing the USDA zone info.


Planting Calendar for Erysimum

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

Erysimum are one of those plants that can tolerate a little bit of cold weather which means that you can plant them earlier than other plants that might not handle the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant erysimum
Possibly ok, but a risky time to plant erysimum
Probably not a good time to plant erysimum

The earliest that you can plant erysimum in Zone 4b 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. You probably don't want to wait any later than that or else 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 little bit earlier.

Last Frost Date

On average all chance of frost has passed is on May 15 in Zone 4b. In the coldest months of winter you should expect an average low temperature of -25°F.

It's important to remember that USDA zone info for Zone 4b may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Zone 4b you get surprised by a frost after May 15 be ready to protect your erysimum in the event of a surprise late frost.

USDA Zone Info for Zone 4b

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 Zone 4b

You may be interested in your other planting guides for Zone 4b.