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.

A way of getting a good idea when it's a good idea to plant welsh onion is to refer to the USDA zone info for Downers Grove.

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.

You can plant welsh onion slightly earlier in the year because they do ok in moderate cold.

The earliest that you can plant welsh onion in Downers Grove 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 little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Downers Grove. 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 Downers Grove is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Downers Grove you get a frost after April 15 be ready to protect your welsh onion if you have a surprise late frost.

USDA Zone Info for Downers Grove

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 Downers Grove

You may be interested in your other planting guides for Downers Grove.