One of the first steps you take when you are determining 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.

In Pueblo you can estimate when it's possible to plant onions by checking out 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.

Onions do well in cold which tells us that you can plant them a quite a bit earlier than other frost tender plants.

The earliest that you can plant onions in Pueblo 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. You probably don't want to wait any later than that or else your onions may not have a chance to fully mature. Starting your onions indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Pueblo. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Pueblo is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Pueblo there is a last frost after April 15 be ready to cover your onions in the event of one of those late frosts.

USDA Zone Info for Pueblo

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 Pueblo

You may be interested in your other planting guides for Pueblo.