One of the best tools that you have as gardeners to help us estimate 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.

You should be able to determine when it's a good idea to plant romanesco by reviewing the USDA zone info for Prosser.

Planting Calendar for Romanesco

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

Romanesco do well in moderate cold which tells us that you can get them planted earlier than plants that are more sensitive to the cold.

The earliest that you can plant romanesco in Prosser 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. If you wait any later than that and your romanesco may not have a chance to really do well. If you are starting your romanesco indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Prosser the average date of last frost happens on April 15. It might get as low as 0°F during the coldest months of winter.

Always keep in mind that USDA zone info for Prosser is not always accurate and the actual date of last frost is different every year. Half of the time in Prosser you get a frost after April 15 so make sure that you are prepared to protect your romanesco in the event of one of those late frosts.

USDA Zone Info for Prosser

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Prosser

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