When to Plant Erysimum in Johnstown, CO

The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of estimating when it's a good idea to plant erysimum is to refer to the USDA zone info for Johnstown.


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 get them planted earlier than plants that are more sensitive to 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 Johnstown 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. Starting your erysimum indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Johnstown and it is different every year. Since half of the time in Johnstown you get surprised by a frost after April 15 be ready to protect your erysimum in the event of a late frost.

USDA Zone Info for Johnstown

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 Johnstown

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