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.

By looking at the USDA zone info for Highland Park it's possible to determine when it's the best time to plant onions.

Planting Calendar for Onions

Frost tolerance for onions:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Onions do well in cold weather which tells us that you can plant them earlier in the year than more sensitive plants.

The earliest that you can plant onions in Highland Park is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant onions and expect a good harvest is probably September. Any later than that and your onions may not have a chance to fully mature. You can get started a few weeks earlier by starting your onions indoors.

Last Frost Date

On average the last frost is on April 15 in Highland Park. In the coldest months of winter you can expect an average low temperature of 0°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Highland Park and it is different every year. Since half of the time in Highland Park it frosts late in the year after April 15 be ready to cover your onions if you have one of those late frosts.

USDA Zone Info for Highland Park

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Highland Park

You may be interested in your other planting guides for Highland Park.