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Thursday - October 23, 2008

From: Great Neck , NY
Region: Northeast
Topic: Container Gardens, Water Gardens, Herbs/Forbs
Title: Overwintering a Juncus effusus in Great Neck, NY
Answered by: Barbara Medford


Can I over winter a juncus effusus spiralis indoors or must it be kept outdoors? Whether indoors or outdoors, what is the proper way to keep it alive during the winter months?


Juncus effusus (common rush) is native to New York and is hardy from USDA Zones 4 to 10. It appears that Great Neck, New York is in Zones 6b to 7a, so the plant should certainly survive 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. 

Pictures of Juncus effusus 'Spiralis'


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