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 USDA zone info for Marseilles should be reffered to in order to figure out when it's the best time to plant zinnia.

Planting Calendar for Zinnia

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

It's probably not a good idea to plant zinnia until after the last frost because they do not do well in cold weather.

The earliest that you can plant zinnia in Marseilles 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. You probably don't want to wait any later than that or else your zinnia may not have a chance to fully mature. If you are starting your zinnia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Marseilles. In the coldest months of winter you should expect an average low temperature of -15°F.

It's important to remember that USDA zone info for Marseilles is an average and the actual date of last frost will vary from year to year. Since half of the time in Marseilles it frosts late in the year after April 15 be ready to cover your zinnia in the event of a surprise late frost.

USDA Zone Info for Marseilles

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 Marseilles

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