When to Plant Erysimum in Harwood Heights, IL

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 Harwood Heights should be figured out by looking at 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.

Since erysimum are moderately cold tolerant you can plant them just a bit earlier in the year than more sensitive plants.

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 Harwood Heights 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. 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 little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Harwood Heights. In the coldest months of winter you should expect an average low temperature of -15°F.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Harwood Heights and it can change quite a bit from year to year. Half of the time in Harwood Heights you get a frost after April 15 so be sure to be ready to protect your erysimum in the event of a late frost.

USDA Zone Info for Harwood Heights

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 Harwood Heights

You may be interested in your other planting guides for Harwood Heights.