Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In North Chicago you can figure out when it's possible to plant petunias by using the USDA zone info.

Planting Calendar for Petunias

Frost tolerance for petunias:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Petunias do ok in moderate cold which tells us that you can plant them slightly earlier than plants that are more sensitive to the cold.

The earliest that you can plant petunias in North Chicago 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 petunias and expect a good harvest is probably August. If you wait any later than that and your petunias may not have a chance to grow to maturity. Starting your petunias indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In North Chicago the average date of last frost happens on April 15. 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 North Chicago may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in North Chicago you get a frost after April 15 be ready to cover your petunias in the event of a surprise late frost.

USDA Zone Info for North Chicago

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 North Chicago

You may be interested in your other planting guides for North Chicago.