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

A common way of determining when to plant radicchio is to use the USDA zone info for Ottumwa.

Planting Calendar for Radicchio

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

You can plant radicchio just a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant radicchio in Ottumwa 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 radicchio and expect a good harvest is probably September. If you wait any later than that and your radicchio may not have a chance to grow to maturity. You can get started a little bit earlier by starting your radicchio indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Ottumwa. It might get as low as -15°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is 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 just be sure to be ready to protect your radicchio if you have a late frost.

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.