One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant romanesco in Washington should be estimated by reviewing the USDA zone info.

Planting Calendar for Romanesco

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

Romanesco are moderately cold tolerant which tells us that you can plant them a little bit earlier than other plants that might not handle the cold.

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

Last Frost Date

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

Keep in mind that USDA zone info for Washington may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Washington there is a last frost after April 15 so just be sure to be ready to protect your romanesco in the event of one of those late frosts.

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.