One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant bunching onions in Phoenix should be estimated by referring to the USDA zone info.

Planting Calendar for Bunching Onions

Frost tolerance for bunching onions:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Bunching Onions are barely cold tolerant which tells us that you can start planting them slightly earlier than plants that are more sensitive to the cold.

The earliest that you can plant bunching onions in Phoenix is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant bunching onions and expect a good harvest is probably August. You probably don't want to wait any later than that or else your bunching onions may not have a chance to grow to maturity. Starting your bunching onions indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Phoenix the average date of last frost happens on March 15. You can expect an average low temperature of 10°F in the coldest months of winter.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Phoenix and it is different every year. Half of the time in Phoenix you get a frost after March 15 so make sure that you are ready to protect your bunching onions in the event of a surprise late frost.

USDA Zone Info for Phoenix

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Phoenix

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