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.

The first chance to plant welsh onion in Carol Stream should be determined by reviewing the USDA zone info.

Planting Calendar for Welsh onion

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

Since welsh onion do ok in moderate cold you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant welsh onion in Carol Stream 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 welsh onion and expect a good harvest is probably August. Any later than that and your welsh onion may not have a chance to really do well. Starting your welsh onion indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Carol Stream. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Carol Stream may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Carol Stream you get surprised by a frost after April 15 so be sure to be ready to protect your welsh onion in the event of a late frost.

USDA Zone Info for Carol Stream

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 Carol Stream

You may be interested in your other planting guides for Carol Stream.