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

A common way of determining when to plant romanesco is to look at the USDA zone info for Elmhurst.

Planting Calendar for Romanesco

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

Since romanesco do well in moderate cold you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant romanesco in Elmhurst 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 fully mature. 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

In Elmhurst 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 Elmhurst is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Elmhurst there is a last frost after April 15 so make sure that you are ready to cover your romanesco in the event of a late frost.

USDA Zone Info for Elmhurst

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 Elmhurst

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