The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Issaquah should be used to figure out when it's the best time to plant radicchio.

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 a little bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant radicchio in Issaquah 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 really do well. You can get started a couple of weeks earlier by starting your radicchio indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Issaquah. You can expect an average low temperature of 15°F in the coldest months of winter.

Since the USDA zone info for Issaquah is an average the actual date of last frost changes from year to year. Since half of the time in Issaquah you get a frost after March 15 be ready to protect your radicchio in the event of a late frost.

USDA Zone Info for Issaquah

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Issaquah

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