When to Plant Coleus in Seattle, WA

Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant coleus in Seattle can be determined by looking at the USDA zone info.


Planting Calendar for Coleus

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

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

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

The earliest that you can plant coleus 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 coleus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your coleus may not have a chance to fully mature. Starting your coleus indoors is a great way to get them started a little bit 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.

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 you get surprised by a frost after March 15 so just be sure to be ready to cover your coleus in the event of a late frost.

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.