Before planting it is a good idea to find your USDA Zone info to determine 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 Des Plaines can be used to estimate when it's possible to plant catharanthus.

Planting Calendar for Catharanthus

Frost tolerance for catharanthus:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

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

The earliest that you can plant catharanthus in Des Plaines 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 catharanthus and expect a good harvest is probably August. If you wait any later than that and your catharanthus may not have a chance to fully mature. If you are starting your catharanthus indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Des Plaines. You can expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that USDA zone info for Des Plaines may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Des Plaines you get a frost after April 15 so make sure that you are ready to protect your catharanthus in the event of a late frost.

USDA Zone Info for Des Plaines

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 Des Plaines

You may be interested in your other planting guides for Des Plaines.