Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to determine when it's a good idea to plant angel's trumpets by reviewing the USDA zone info for Ottumwa.

Planting Calendar for Angel's Trumpets

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

Since angel's trumpets are barely cold tolerant you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant angel's trumpets 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 angel's trumpets and expect a good harvest is probably August. If you wait any later than that and your angel's trumpets may not have a chance to fully mature. Starting your angel's trumpets indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Ottumwa and it is different every year. Half of the time in Ottumwa you get surprised by a frost after April 15 so make sure that you are ready to cover your angel's trumpets in the event of 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.