When to Plant Hemerocallis in Rockville, MD

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

A way of getting a good idea when it's the best time to plant hemerocallis is to use the USDA zone info for Rockville.


Planting Calendar for Hemerocallis

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

Hemerocallis do well in moderate cold which means that you can plant them earlier 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 Rockville 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. If you wait any later than that and your hemerocallis may not have a chance to really do well. Starting your hemerocallis 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 April 15 in Rockville. You can expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Rockville is not always accurate the actual date of last frost will vary from year to year. Half of the time in Rockville it frosts late in the year after April 15 so always be ready to cover your hemerocallis in the event of a surprise late frost.

USDA Zone Info for Rockville

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low0°F
Highest Expected Low5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Rockville

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