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Thursday - November 18, 2010

From: Bellevue, WA
Region: Northwest
Topic: Pruning, Seasonal Tasks, Grasses or Grass-like
Title: Cutting Juncus effusus back from Bellevue WA
Answered by: Barbara Medford

QUESTION:

I read your posts about Juncus effusus and just have one follow-up question. When is the best time to cut them back to the ground - before winter or early spring? I live in the Pacific NW. I recently divided a large juncus (apparently wasn't supposed to until spring.) If it should survive, when is the appropriate time of year to cut it down to ground level to promote new growth? Thank you for your time.

ANSWER:

Juncus effusus (Common rush) is native to Washington State, but King County is one of those areas with incredibly complex USDA Hardiness Zones, in this case ranging from Zones 6a to 8a. This USDA Plant Profile does not show this particular juncus as growing in King County, in the central eastern portion of Washington. However, these USDA maps are often out of date, and we believe the plant should be hardy in your garden.

From Floridata, we found this site on Juncus effusus, which does, indeed, indicate that the plant should be divided in Spring. However, with its underground rhizomes, it would probably take a lot more than premature division to kill it. Because you live in a mild climate, it really is only necessary to cut it back when it become unattractive, usually in the winter.

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