The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of estimating when it's the best time to plant purple coneflower is to refer to the USDA zone info for Mountlake Terrace.

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 tells us that you can plant them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant purple coneflower in Mountlake Terrace 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. If you wait 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 has passed is on March 15 in Mountlake Terrace. You can expect an average low temperature of 15°F in the coldest months of winter.

Since the USDA zone info for Mountlake Terrace may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Mountlake Terrace last frost occurs after March 15 so make sure that you are prepared to protect your purple coneflower if you have a surprise late frost.

USDA Zone Info for Mountlake Terrace

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 Mountlake Terrace

You may be interested in your other planting guides for Mountlake Terrace.