When to Plant Oenothera in Granite City, IL

One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to estimate when you can plant oenothera by referring to the USDA zone info for Granite City.


Planting Calendar for Oenothera

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

You can plant oenothera a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

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

The earliest that you can plant oenothera in Granite City 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 oenothera and expect a good harvest is probably September. Any later than that and your oenothera may not have a chance to grow to maturity. Starting your oenothera indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Granite City the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Granite City is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Granite City you get a frost after April 15 be ready to protect your oenothera if you have one of those late frosts.

USDA Zone Info for Granite City

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-5°F
Highest Expected Low0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Granite City

You may be interested in your other planting guides for Granite City.