One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to estimate when it's the best time to plant tree onions by checking out the USDA zone info for Lake Zurich.

Planting Calendar for Tree onions

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

Tree onions are barely cold tolerant which means that you can get them planted just a bit earlier than more sensitive plants.

The earliest that you can plant tree onions in Lake Zurich 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 tree onions and expect a good harvest is probably August. You probably don't want to wait any later than that or else your tree onions may not have a chance to fully mature. Starting your tree onions indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Lake Zurich the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Lake Zurich is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Lake Zurich you get surprised by a frost after April 15 be ready to protect your tree onions in the event of one of those late frosts.

USDA Zone Info for Lake Zurich

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 Lake Zurich

You may be interested in your other planting guides for Lake Zurich.