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.

In Ottumwa you can figure out when you can plant calibrachoa by reviewing the USDA zone info.

Planting Calendar for Calibrachoa

Frost tolerance for calibrachoa:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant calibrachoa slightly earlier in the year because they do ok in moderate cold.

The earliest that you can plant calibrachoa in Ottumwa is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant calibrachoa and expect a good harvest is probably August. If you wait any later than that and your calibrachoa may not have a chance to really do well. Starting your calibrachoa indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Ottumwa is just an average the actual date of last frost will vary from year to year. Half of the time in Ottumwa there is a last frost after April 15 so always be ready to protect your calibrachoa if you have one of those late frosts.

USDA Zone Info for Ottumwa

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 Ottumwa

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