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

You can determine when it's the best time to plant bunching onions in Winnetka by referring to the USDA zone info.

Planting Calendar for Bunching Onions

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

Bunching Onions do ok in some cold which means that you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant bunching onions in Winnetka 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 bunching onions and expect a good harvest is probably August. If you wait any later than that and your bunching onions may not have a chance to really do well. You can get started a little bit earlier by starting your bunching onions indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Winnetka. You should expect an average low temperature of -15°F in the coldest months of winter.

It's important to remember that USDA zone info for Winnetka is just an average and the actual date of last frost is different every year. Half of the time in Winnetka last frost occurs after April 15 so make sure that you are ready to cover your bunching onions in the event of a late frost.

USDA Zone Info for Winnetka

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 Winnetka

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