One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

By referring to the USDA zone info for Phoenix it's possible to estimate when it's possible to plant scallions.

Planting Calendar for Scallions

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

Scallions can survive in mild cold which means that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant scallions 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 scallions and expect a good harvest is probably August. Any later than that and your scallions may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your scallions indoors.

Last Frost Date

On average the last frost is on March 15 in Phoenix. In the coldest months of winter you can expect an average low temperature of 10°F.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Phoenix and it changes from year to year. Since half of the time in Phoenix last frost occurs after March 15 be ready to protect your scallions 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.