The USDA Zone info is a great tool for gardeners to help us figure out 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 USDA zone info for Sahuarita can be reffered to in order to determine when it's possible to plant tree onions.

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 can survive in mild cold which means that you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant tree onions in Sahuarita 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 tree onions and expect a good harvest is probably September. If you wait any later than that and your tree onions may not have a chance to really do well. Starting your tree onions indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Sahuarita. It might get as low as 20°F during the coldest months of winter.

Since the USDA zone info for Sahuarita is an average the actual date of last frost changes from year to year. Since half of the time in Sahuarita you get surprised by a frost after February 15 be ready to cover your tree onions in the event of a surprise late frost.

USDA Zone Info for Sahuarita

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Sahuarita

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