When to Plant Amaranthus in Seattle, WA

One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when it's the best time to plant amaranthus in Seattle by checking out the USDA zone info.


Planting Calendar for Amaranthus

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

It's a bad idea to plant amaranthus until after all chance of frost has passed because they do not do well in cold weather.

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 Seattle 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 grow to maturity. 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

The average date of last frost is March 15 in Seattle. In the coldest months of winter you can expect an average low temperature of 15°F.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Seattle and it will vary from year to year. Half of the time in Seattle last frost occurs after March 15 so make sure that you are prepared to protect your amaranthus if you have one of those late frosts.

USDA Zone Info for Seattle

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 Seattle

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