Explore Plants

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
    
 

Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.

rate this answer
Not Yet Rated

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 However, these USDA maps are often out of date, and we believe the plant should be hardy in your garden.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.

From our Native Plant Image Gallery:

 

 

More Grasses or Grass-like Questions

killing grass on 1 acre before planting Habiturf
March 04, 2012 - I have an acre of full sun lawn on a slight slope in Dallas - would the habiturf be appropriate & if so, how do I go about killing off the existing weeds/crab grass before installing? Removing 3 in o...
view the full question and answer

Solarization and hand-pulling to remove invasive weeds
June 20, 2004 - We are planting a field of native grasses, and prepared the landscape by solarization last July. However it now seems that the weeds returned with great vigor. Is there any other method to get rid of ...
view the full question and answer

Native grasses for a sandy Maryland yard
June 10, 2011 - Mr. Smarty Plants, I live in Severn (AA County) where we have sandy soil and on a well/septic system. Can you tell me a native grass I can seed in my yard? Something hardy and does not require a ...
view the full question and answer

Native sedges for Texas
March 07, 2007 - What can you tell me about Texas Blue Sedge? What its true name and culture requirements?
view the full question and answer

Can fibrous roots of Chasmanthium latifolium damage house foundation
May 03, 2013 - Dear Mr.Ms. S-P, Can the fibrous roots of inland sea oats cause foundation problems? I was digging around my foundation and found a root about 1" in diameter that I am afraid might be from sea oa...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.