One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can estimate when it's the best time to plant welsh onion in Clarendon Hills 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.

Welsh onion do ok in moderate cold which tells us that you can start planting them slightly earlier than other frost tender plants.

The earliest that you can plant welsh onion in Clarendon Hills 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. You can get started a couple of weeks earlier by starting your welsh onion indoors.

Last Frost Date

The average date of last frost is April 15 in Clarendon Hills. It might get as low as -15°F during the coldest months of winter.

It's important to remember that USDA zone info for Clarendon Hills is not always accurate and the actual date of last frost is different every year. Half of the time in Clarendon Hills last frost occurs after April 15 so be sure to be ready to protect your welsh onion if you have a late frost.

USDA Zone Info for Clarendon Hills

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 Clarendon Hills

You may be interested in your other planting guides for Clarendon Hills.