One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of figuring out when it's the best time to plant tree onions is to consult the USDA zone info for Hidalgo.

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 do ok in moderate cold which means that you can start planting them slightly earlier than plants that are more sensitive to the cold.

The earliest that you can plant tree onions in Hidalgo 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. You probably don't want to wait any later than that or else your tree onions may not have a chance to really do well. If you are starting your tree onions indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Hidalgo. It might get as low as 25°F during the coldest months of winter.

Keep in mind that USDA zone info for Hidalgo is not always accurate and the actual date of last frost changes from year to year. Half of the time in Hidalgo last frost occurs after February 15 so just be sure to be ready to protect your tree onions in the event of a late frost.

USDA Zone Info for Hidalgo

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Hidalgo

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