Host an Event Volunteer Join Tickets

Support the plant database you love!

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Share

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
1 rating

Monday - June 28, 2010

From: Mountville, PA
Region: Mid-Atlantic
Topic: Water Gardens, Seasonal Tasks
Title: Can Juncus effusus winter outside in Mountville PA?
Answered by: Barbara Medford

QUESTION:

If we have the juncus effusus spiralis outside in a small pond and you say to let it outside in the winter does that mean we should let it in the pond? thanks for your time

ANSWER:

Juncus effusus (common rush) is native to nearly all the states and some Canadian provinces in North America, including Texas and Pennsylvania.  We are a little confused; was your question should you leave it outside and leave it in the pond? When you say "let" we think more of letting the dog in, so should you let the plant in? 

 

Juncus effusus (common rush)  is hardy from USDA Zones 4 to 10. It appears that Mountville PA, Lancaster County is in Zones 6a to 6b, so the plant should do fine there outside. Juncus effusus 'Spiralis' is a selection for horticultural use, low growing with strongly spiraling stems. According to this Floridata article on Juncus effusus, it is really better to allow the plant to freeze back, remaining outdoors during the winter, because the stems (there are no leaves) will come back much stronger and better-looking. In milder climates (such as indoors) the stems will get brown and less attractive-looking, and will need to be trimmed. However, this page from Blue Stem Nursery on Lesser Corkscrew Rush refers to it as a plant that can be kept in a terra cotta pot and double as a winter houseplant. We would imagine the soil in the pot would need to be kept pretty moist, but we did see a number of illustrations of the plant in pots and indoors. 

As to whether to leave it in the pond outdoors in winter, that probably depends on how hard your pond freezes. The plant needs to be kept moist, frozen or not, so you will have to use your best judgment on whether to pot it up and bring it where you  can water it outside if it's not getting enough moisture, or bring it inside and give it moisture. 

Pictures of Juncus effusus 'Spiralis' 

 

 

More Seasonal Tasks Questions

Winter-hardiness of hibiscus in Idaho
June 14, 2009 - I bought a hibiscus tree at Sam's Club in Idaho Falls and after planting it, I read the label which says not to go below 50 degrees. Does that mean it is an inside or potted tree to bring in in the ...
view the full question and answer

Sycamore leaf snowbell from Pleasanton TX
August 18, 2012 - How do you care for a sycamore leaf snowbell. Does it like sun or part shade? How much water? How often and what should it be fed. How fast or slowly does it grow? Anything you can tell me would be ap...
view the full question and answer

Moving a red oak away from the house foundation
January 24, 2008 - About a 3 weeks ago I noticed a 5 ft. red oak growing in my flower bed. I hadn't noticed it growing up through my shrubs until the leaves turned bright red. The problem is that its coming up about tw...
view the full question and answer

Recreating a wildflower meadow, central Texas
July 02, 2013 - We have an acre on our property that has bluebonnets. Unfortunately, it also has other plants that we don't want -Johnson grass, nettles, burrs. We plan to do a controlled burn in the fall and re-...
view the full question and answer

Cutting Back Perennials in the Fall?
November 13, 2013 - We have large beds of flowering native perennials that we planted around our house as part of a landscape conservation plan (various Joe-Pyes, goldenrods, turtlehead, blazing star, brown-eyed Susans)....
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.