When to Plant Pearl onions in Rockford, IL

Before planting it is a good idea to find your USDA Zone info to figure out 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.

In Rockford you can determine when it's a good idea to plant pearl onions by using the USDA zone info.


Planting Calendar for Pearl onions

Frost tolerance for pearl onions: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Since pearl onions do ok in moderate cold you can plant them just a tiny bit earlier in the year than more sensitive plants.

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

The earliest that you can plant pearl onions in Rockford 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 pearl onions and expect a good harvest is probably August. Any later than that and your pearl onions may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your pearl onions indoors.

Last Frost Date

The average date of last frost is April 15 in Rockford. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Rockford may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Rockford there is a last frost after April 15 so just be sure to be ready to cover your pearl onions if you have one of those late frosts.

USDA Zone Info for Rockford

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 Rockford

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