The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of getting a good idea when you can plant romanesco is to use the USDA zone info for Zone 4b.

Planting Calendar for Romanesco

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

You can plant romanesco just a bit earlier in the year because they do well in moderate cold.

The earliest that you can plant romanesco in Zone 4b is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant romanesco and expect a good harvest is probably August. You probably don't want to wait any later than that or else your romanesco may not have a chance to fully mature. You can get started a little bit earlier by starting your romanesco indoors.

Last Frost Date

On average the last frost has passed is on May 15 in Zone 4b. In the coldest months of winter you can expect an average low temperature of -25°F.

Since the USDA zone info for Zone 4b is just an average the actual date of last frost is different every year. Half of the time in Zone 4b there is a last frost after May 15 so be sure to be ready to cover your romanesco in the event of a late frost.

USDA Zone Info for Zone 4b

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Zone 4b

You may be interested in your other planting guides for Zone 4b.