The USDA Zone info is a great tool for gardeners to help us figure out your gardening 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 figuring out when it's possible to plant radicchio is to examine the USDA zone info for Humboldt.

Planting Calendar for Radicchio

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

Radicchio tend to make it in a little bit of cold which means that you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant radicchio in Humboldt 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. 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

The average date of last frost is April 15 in Humboldt. In the coldest months of winter you should expect an average low temperature of 0°F.

Always keep in mind that USDA zone info for Humboldt is just an average and the actual date of last frost is different every year. Since half of the time in Humboldt it frosts late in the year after April 15 be ready to cover your radicchio in the event of a surprise late frost.

USDA Zone Info for Humboldt

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Humboldt

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