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

The USDA zone info for Lewiston should be used to figure out when it's a good idea to plant purple coneflower.

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

The earliest that you can plant purple coneflower in Lewiston 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 fully mature. You can get started a few weeks earlier by starting your purple coneflower indoors.

Last Frost Date

In Lewiston the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Lewiston is an average the actual date of last frost will vary from year to year. Half of the time in Lewiston you get surprised by a frost after April 15 so make sure that you are ready to cover your purple coneflower if you have a late frost.

USDA Zone Info for Lewiston

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°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 -10°F.

Plants to Grow in Lewiston

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