Before planting it is a good idea to find your USDA Zone info to determine 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.

You can estimate when to plant osteospermum in Granite City by referring to the USDA zone info.

Planting Calendar for Osteospermum

Frost tolerance for osteospermum:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Osteospermum are one of those plants that can tolerate a little bit of cold weather which means that you can plant them earlier than more sensitive plants.

The earliest that you can plant osteospermum in Granite City 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 osteospermum and expect a good harvest is probably September. If you wait any later than that and your osteospermum may not have a chance to fully mature. Starting your osteospermum indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Granite City the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -5°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Granite City and it changes from year to year. Since half of the time in Granite City there is a last frost after April 15 be ready to cover your osteospermum in the event of a surprise late frost.

USDA Zone Info for Granite City

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Granite City

You may be interested in your other planting guides for Granite City.