The USDA Zone info is a great tool for gardeners to help us estimate 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.

The first chance to plant broccoli in Seattle can be determined by using the USDA zone info.

Planting Calendar for Broccoli

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

You can plant broccoli a little 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 broccoli 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 broccoli and expect a good harvest is probably September. You probably don't want to wait any later than that or else your broccoli may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your broccoli indoors.

Last Frost Date

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

It's important to 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 it frosts late in the year after March 15 so be sure to be ready to cover your broccoli if you have 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.