Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. 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 figure out when you can plant romanesco by looking at the USDA zone info for Smithfield.

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 some cold which means that you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant romanesco in Smithfield 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. You probably don't want to wait any later than that or else your romanesco may not have a chance to grow to maturity. If you are starting your romanesco indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Smithfield. In the coldest months of winter you should expect an average low temperature of -15°F.

Remember that USDA zone info for Smithfield is not always accurate and the actual date of last frost is different every year. Half of the time in Smithfield it frosts late in the year after April 15 so just be sure to be ready to cover your romanesco if you have a surprise late frost.

USDA Zone Info for Smithfield

Here is the info for USDA Zone 5b.

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

Plants to Grow in Smithfield

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