One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You should be able to determine when it's a good idea to plant brussels sprouts by referring to the USDA zone info for Washington.

Planting Calendar for Brussels Sprouts

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

Brussels Sprouts are one of those plants that can tolerate a little bit of cold weather which means that you can start planting them earlier than other frost tender plants.

The earliest that you can plant brussels sprouts in Washington 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 brussels sprouts and expect a good harvest is probably September. Any later than that and your brussels sprouts may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your brussels sprouts indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Washington. It might get as low as -10°F during the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Washington and it changes from year to year. Half of the time in Washington you get surprised by a frost after April 15 so be sure to be ready to protect your brussels sprouts if you have a late frost.

USDA Zone Info for Washington

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Washington

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