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.

The USDA zone info for Sutherlin should be looked at to figure out when it's the best time to plant cosmos.

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.

Cosmos can survive in a tiny bit of cold which tells us that you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant cosmos in Sutherlin 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. If you wait any later than that and your cosmos may not have a chance to fully mature. You can get started a little bit earlier by starting your cosmos indoors.

Last Frost Date

On average the last frost is on March 15 in Sutherlin. It might get as low as 15°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Sutherlin is an average and the actual date of last frost will vary from year to year. Since half of the time in Sutherlin last frost occurs after March 15 be ready to cover your cosmos if you have one of those late frosts.

USDA Zone Info for Sutherlin

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 Low	15°F
Highest Expected Low	20°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 Sutherlin

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