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.

It's possible to estimate when to plant amaranthus by referring to the USDA zone info for Oregon.

Planting Calendar for Amaranthus

Frost tolerance for amaranthus:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's a bad idea to plant amaranthus until after the last frost because they are not cold tolerant.

The earliest that you can plant amaranthus in Oregon is April. However, you really should wait until May if you don't want to take any chances.

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

Last Frost Date

On average all chance of frost has passed is on April 15 in Oregon. In the coldest months of winter you should expect an average low temperature of -20°F.

Since the USDA zone info for Oregon is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Oregon you get surprised by a frost after April 15 be ready to cover your amaranthus in the event of a surprise late frost.

USDA Zone Info for Oregon

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°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 -15°F.

Plants to Grow in Oregon

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