One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Iowa Falls should be used to estimate when to plant osteospermum.

Planting Calendar for Osteospermum

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

Since osteospermum are moderately cold tolerant you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant osteospermum in Iowa Falls 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 grow to maturity. You can get started a few weeks earlier by starting your osteospermum indoors.

Last Frost Date

In Iowa Falls the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -20°F.

Since the USDA zone info for Iowa Falls is just an average the actual date of last frost changes from year to year. Half of the time in Iowa Falls there is a last frost after April 15 so be sure to be ready to protect your osteospermum in the event of a late frost.

USDA Zone Info for Iowa Falls

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Iowa Falls

You may be interested in your other planting guides for Iowa Falls.