Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's possible to figure out when it's possible to plant amaranthus by referring to the USDA zone info for Phoenix.

Planting Calendar for Amaranthus

Frost tolerance for amaranthus:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since amaranthus do not do well in cold weather you really should wait until after the last frost has passed before you can plant them.

The earliest that you can plant amaranthus 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 amaranthus and expect a good harvest is probably September. If you wait any later than that and your amaranthus may not have a chance to fully mature. If you are starting your amaranthus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Phoenix the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Always keep in mind that USDA zone info for Phoenix may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Phoenix there is a last frost after February 15 so make sure that you are prepared to protect your amaranthus in the event of a late frost.

USDA Zone Info for Phoenix

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 Phoenix

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