When to Plant Amaranthus in Portland, OR

Before planting it is a good idea to find your USDA Zone info to figure out 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.

The first opportunity to plant amaranthus in Portland can be determined by using the USDA zone info.


Planting Calendar for Amaranthus

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

Amaranthus are not cold tolerant which means that it is important to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant amaranthus
Possibly ok, but a risky time to plant amaranthus
Probably not a good time to plant amaranthus

The earliest that you can plant amaranthus in Portland 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. Any later than that and your amaranthus may not have a chance to really do well. If you are starting your amaranthus indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is March 15 in Portland. It might get as low as 15°F during the coldest months of winter.

Keep in mind that USDA zone info for Portland is an average and the actual date of last frost changes from year to year. Half of the time in Portland you get a frost after March 15 so make sure that you are prepared to protect your amaranthus in the event of a surprise late frost.

USDA Zone Info for Portland

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)March 15
Average Date of First Frost (fall)November 15
Lowest Expected Low15°F
Highest Expected Low20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Portland

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