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

It's a good idea to determine when you can plant purple coneflower by referring to the USDA zone info for Snohomish.

Planting Calendar for Purple Coneflower

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

Purple Coneflower are barely cold tolerant which means that you can get them planted just a bit earlier than other plants that might not handle the cold.

The earliest that you can plant purple coneflower in Snohomish 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 purple coneflower and expect a good harvest is probably August. Any later than that and your purple coneflower may not have a chance to grow to maturity. Starting your purple coneflower indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Remember that USDA zone info for Snohomish is just an average and the actual date of last frost will vary from year to year. Since half of the time in Snohomish you get a frost after March 15 be ready to cover your purple coneflower if you have a late frost.

USDA Zone Info for Snohomish

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 Snohomish

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