One of the first steps you take when you are estimating 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.

One way of estimating when to plant coreopsis is to check out the USDA zone info for Ellensburg.

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 one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant coreopsis in Ellensburg 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 really do well. You can get started a few weeks earlier by starting your coreopsis indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Ellensburg. In the coldest months of winter you should expect an average low temperature of -5°F.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Ellensburg and it changes from year to year. Since half of the time in Ellensburg you get a frost after April 15 be ready to protect your coreopsis in the event of a surprise late frost.

USDA Zone Info for Ellensburg

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Ellensburg

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