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

The USDA zone info for Marengo should be used to determine when it's a good idea to plant romanesco.

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 means that you can plant them earlier than more sensitive plants.

The earliest that you can plant romanesco in Marengo 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 really do well. You can get started a few weeks earlier by starting your romanesco indoors.

Last Frost Date

In Marengo the average date of last frost happens on April 15. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Marengo is an average the actual date of last frost is different every year. Half of the time in Marengo it frosts late in the year after April 15 so be sure to be ready to cover your romanesco in the event of one of those late frosts.

USDA Zone Info for Marengo

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 Marengo

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