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
5 ratings

Monday - October 08, 2007

From: Bonn, Germany
Region: Other
Topic: Propagation
Title: Western red cedar (Thuja plicata) frost tolerance, making cuttings
Answered by: Nan Hampton

QUESTION:

Dear Madam or Sir, It would be very kind, if you could answer my questions about the “Thuja Plicata atrovirens” alias “Western Red Cedar”. I need the information because a good friend of mine planted several remarkable cedars in his garden. It would be a pity if they are damaged by an incorrect treatment. First some information regarding the cedars: They were planted in 2003 and 2005. The length of the plants was approximately 7 ft. Now they are ca. 16 feet. They are supposed to grow to a length of 19 feet. The calibre at the ground is around 6.5 ft. The green part has 1 ft. The location is very sunny. The ground has big part topsoil, turf and sand. When they were planted a distance of 2.6 feet between the logs was kept. They already look like a hedge. No cuttings have been taken so far. Climate: Continental Europe / Central European My questions: When would be the best time to take cuttings? How often is it possible to take cuttings during a year? How much of the green part can be cut? How frost resistant are the roots? We plan to build a slope near the cedars and for this reason the roots, at one of the sides, will only have 1 meter (3 feet) soil (from the logs to the border of the slope). Can the roots possibly compensate for the frost risk exposed to the part, which is not experiencing optimal protection? Besides the aforementioned questions I would be very interested in further information regarding the Red Western Cedar. I am looking forward hearing from you and thank you in advance. Best regards

ANSWER:

It sounds as if your friend's western red cedars are doing very well to have doubled their height in four years time.

Thuja plicata (western red cedar) is native to the northwestern United States, Canada and southwestern Alaska.

I am including references with more information about Thuja plicata from Washington State, The Gymnosperm Database, Glacier National Park and the Center for Wood Anatomy Research of the US Forest Service.

When you speak of taking cuttings, I am not sure whether you mean: 1. when and how to prune the trees for shaping, or 2. how to take cuttings for propagating the trees vegetatively.

Most sources say that T. plicata doesn't require pruning but will tolerate it if you want to make it a different shape or size.

There is lots of information about propagating T. plicata from seeds, but very little about vegetative propagation. The one source I found, Plants for a Future, recommends taking cuttings of half-ripe wood, 5-8cm with a heel in July/August and rooting in a shaded frame. Roots should form by the end of September but it should be overwintered in a frame. Alternatively, cuttings of almost ripe wood, 5-10cm with a heel, can be taken in September and rooted in a cold frame. Roots should form by the following summer and be planted out in autumn or spring. Here is a little more information about Plant Propagation by Stem Cuttings: Instructions for the Home Gardener.

With regards to the frost tolerance of the roots, Western red cedar survives in Ketchikan, Alaska with an average minumum temperature of 28.3 degrees F. in January, which is not too different from Bonn, Germany where the average minimum temperature in January is 31 degrees F. Unless you are exposing the roots completely, I would think that they could withstand the frost as long as they had at least a meter of soil covering them since I wouldn't think the soil would freeze down to 1 meter in Bonn's climate.

 



 

 

More Propagation Questions

Propagation and transplanting of Vernonia lindheimeri
April 10, 2007 - I have located a wooly ironweed plant and have taken some seeds to start. This is the only ironweed I have seen. Any suggestions on how to start the seed? Also, if development of the property appea...
view the full question and answer

Reproducing Echinacea 'Sunbeam' from Powthan VA
August 03, 2011 - I would like to reproduce a flowering plant- Sundown echinacea. I have a plant now. Can you give me info on how to do it? thanks so much.
view the full question and answer

What to do with agave after it blooms from Phoenix AZ
March 12, 2013 - Hello! I have 2 century plants in the process of blooming. How exciting!! I've never really seen it before. Anyway, what do I then do with the dying/dead plant. Simply dig it up and trash it? T...
view the full question and answer

No berries on dogwoods in GA
November 18, 2010 - I have 4 native dogwood trees. I have owned the property for 4 years. They have never produced berries. Can you tell me why? are the trees male and female, and could I have all males?
view the full question and answer

Propagating mimosa from seed
October 09, 2008 - I have a seed pod from a Mimosa tree. What is the best way to start this beautiful tree from seed. Thank you!
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.