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.

By looking at the USDA zone info for Park Ridge it's a good idea to estimate when to plant zinnia.

Planting Calendar for Zinnia

Frost tolerance for zinnia:	Not tolerant of frost.
When to plant:	After the last frost has passed.

It's a bad idea to plant zinnia until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant zinnia in Park Ridge is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant zinnia and expect a good harvest is probably August. If you wait any later than that and your zinnia may not have a chance to really do well. If you are starting your zinnia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Park Ridge. It might get as low as -15°F during the coldest months of winter.

It's important to remember that USDA zone info for Park Ridge is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Park Ridge it frosts late in the year after April 15 be ready to protect your zinnia in the event of one of those late frosts.

USDA Zone Info for Park Ridge

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 Park Ridge

You may be interested in your other planting guides for Park Ridge.