One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to determine when it's possible to plant creeping zinnia by looking at the USDA zone info for Kennewick.

Planting Calendar for Creeping Zinnia

Frost tolerance for creeping zinnia:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant creeping zinnia slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant creeping zinnia in Kennewick is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant creeping zinnia and expect a good harvest is probably August. Any later than that and your creeping zinnia may not have a chance to really do well. If you are starting your creeping zinnia indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Kennewick the average date of last frost happens on April 15. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Kennewick is just an average the actual date of last frost will vary from year to year. Half of the time in Kennewick you get a frost after April 15 so make sure that you are prepared to cover your creeping zinnia if you have a surprise late frost.

USDA Zone Info for Kennewick

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Kennewick

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