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When to Plant Hemerocallis 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 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 Rock Springs should be read to figure out when to plant hemerocallis.


Planting Calendar for Hemerocallis

Frost tolerance for hemerocallis: Tolerant of some frost.
When to plant: Up to 5 weeks before last frost.

Since hemerocallis are moderately cold tolerant you can plant them a little earlier in the year than other frost tender plants.

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

The earliest that you can plant hemerocallis in Rock Springs is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant hemerocallis and expect a good harvest is probably September. You probably don't want to wait any later than that or else your hemerocallis may not have a chance to really do well. If you are starting your hemerocallis indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Rock Springs the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Rock Springs and it can change quite a bit from year to year. Half of the time in Rock Springs you get surprised by a frost after April 15 so make sure that you are ready to cover your hemerocallis if you have a surprise late frost.

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.