When to Plant Coreopsis in Issaquah, WA

One of the best tools that you have as gardeners to help us determine 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.

One way of making a decision about when it's a good idea to plant coreopsis is to check out the USDA zone info for Issaquah.


Planting Calendar for Coreopsis

Frost tolerance for coreopsis: Tolerant of some frost.
When to plant: Up to 5 weeks before last frost.

You can plant coreopsis a little bit earlier in the year because they are moderately cold tolerant.

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

The earliest that you can plant coreopsis in Issaquah is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant coreopsis and expect a good harvest is probably September. If you wait any later than that and your coreopsis may not have a chance to fully mature. Starting your coreopsis indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Issaquah may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Issaquah you get surprised by a frost after March 15 be ready to cover your coreopsis if you have a late frost.

USDA Zone Info for Issaquah

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 Issaquah

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