When to Plant Amaranthus in Mercer Island, WA

One of the first steps you take when you are making a decision about your gardening schedule is find your 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 reviewing the USDA zone info for Mercer Island it's a good idea to figure out when it's possible to plant amaranthus.


Planting Calendar for Amaranthus

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

It's probably not a good idea to plant amaranthus until after the last frost when the weather gets warmer because they are not cold tolerant.

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 Mercer Island 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. Starting your amaranthus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Remember that USDA zone info for Mercer Island is an average and the actual date of last frost is different every year. Half of the time in Mercer Island you get surprised by a frost after March 15 so make sure that you are ready to cover your amaranthus in the event of one of those late frosts.

USDA Zone Info for Mercer Island

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 Mercer Island

You may be interested in your other planting guides for Mercer Island.