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

You can determine when you can plant cosmos in Kennewick by checking out the USDA zone info.

Planting Calendar for Cosmos

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

Since cosmos are one of those plants that can tolerate a tiny bit of cold weather you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant cosmos 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 cosmos and expect a good harvest is probably August. Any later than that and your cosmos may not have a chance to grow to maturity. Starting your cosmos indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Kennewick the average date of last frost happens on April 15. You can expect an average low temperature of 0°F in the coldest months of winter.

Always keep in mind that USDA zone info for Kennewick is just an average and the actual date of last frost will vary from year to year. Half of the time in Kennewick you get surprised by a frost after April 15 so make sure that you are prepared to protect your cosmos if you have one of those late frosts.

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.