One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

One way of estimating when it's possible to plant brussels sprouts is to use the USDA zone info for Seattle.

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 do well in moderate cold which tells us that you can plant them earlier than more sensitive plants.

The earliest that you can plant brussels sprouts in Seattle 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. If you are starting your brussels sprouts indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Seattle and it is different every year. Half of the time in Seattle there is a last frost after March 15 so make sure that you are prepared to cover your brussels sprouts in the event of a surprise late frost.

USDA Zone Info for Seattle

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 Seattle

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