When to Plant Romanesco in Harvard, IL

Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to determine when it's possible to plant romanesco by reviewing the USDA zone info for Harvard.


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 other frost tender plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant romanesco
Possibly ok, but a risky time to plant romanesco
Probably not a good time to plant romanesco

The earliest that you can plant romanesco in Harvard 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. 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 Harvard the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Harvard is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Harvard you get a frost after April 15 be ready to cover your romanesco in the event of a late frost.

USDA Zone Info for Harvard

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 Harvard

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