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When to Plant Purple Coneflower in Rock Springs, WY

One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. 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 Rock Springs can be looked at to estimate when it's possible 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 can survive in very little cold which means that you can plant them slightly earlier in the year than other plants that might not handle the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant purple coneflower
Possibly ok, but a risky time to plant purple coneflower
Probably not a good time to plant purple coneflower

The earliest that you can plant purple coneflower in Rock Springs 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 really do well. If you are starting your purple coneflower indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Rock Springs. You should expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Rock Springs is not always accurate the actual date of last frost changes from year to year. Since half of the time in Rock Springs there is a last frost after April 15 be ready to protect your purple coneflower if you have one of those late frosts.

USDA Zone Info for Rock Springs

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Rock Springs

You may be interested in your other planting guides for Rock Springs.