The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant onions in Commerce City can be figured out by referring to the USDA zone info.

Planting Calendar for Onions

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

You can plant onions earlier in the year because they do well in cold.

The earliest that you can plant onions in Commerce City 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 really do well. You can get started a few weeks earlier by starting your onions indoors.

Last Frost Date

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

Since the USDA zone info for Commerce City may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Commerce City last frost occurs after April 15 be ready to cover your onions in the event of one of those late frosts.

USDA Zone Info for Commerce City

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 Commerce City

You may be interested in your other planting guides for Commerce City.