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

The USDA zone info for Casa Grande should be read to estimate when you can 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 are very cold tolerant which tells us that you can plant them a quite a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant onions in Casa Grande 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 really do well. Starting your onions indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Casa Grande the average date of last frost happens on April 15. You should expect an average low temperature of 5°F in the coldest months of winter.

Remember that USDA zone info for Casa Grande is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Casa Grande you get a frost after April 15 so be sure to be ready to protect your onions if you have one of those late frosts.

USDA Zone Info for Casa Grande

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Casa Grande

You may be interested in your other planting guides for Casa Grande.