Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant oenothera in Mount Prospect can be estimated by using the USDA zone info.

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 little earlier in the year because they do well in moderate cold.

The earliest that you can plant oenothera in Mount Prospect 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. You probably don't want to wait any later than that or else your oenothera may not have a chance to grow to maturity. If you are starting your oenothera indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Mount Prospect. You should expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Mount Prospect may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Mount Prospect last frost occurs after April 15 so just be sure to be ready to protect your oenothera in the event of a late frost.

USDA Zone Info for Mount Prospect

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 Mount Prospect

You may be interested in your other planting guides for Mount Prospect.