En EspaŅol

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
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

Sunday - August 01, 2010

From: Mt Pleasant, MI
Region: Midwest
Topic: Shrubs
Title: Dogwood under a black walnut in Mt.Pleasant MI
Answered by: Barbara Medford

QUESTION:

Can I grow red or yellow twigged dogwood near a black walnut?

ANSWER:

You can plant a Cornus sericea (redosier dogwood) anywhere you choose; whether it will thrive or even live more than a year or so under a Juglans nigra (black walnut) is another question entirely. Both are native or near your area of Isabella County, in central Michigan, USDA Hardiness Zones 4a to 5a.

The problem, as you may know, is a characteristic of black walnut to emit juglones, substances intended to discourage or prohibit competition from other plants. We found an excellent article from  Virginia Cooperative Extension Black Walnut and Allelopathy which fully explains this procedure. Even plants some distance away can be affected because every part of the tree exudes the juglones, including roots which may extend 3 times the size of the crown. However, this same article had a chart of plants that were resistant to the effects of allelopathy, including trees and shrubs. On this chart of resistant plants "dogwood, flowering" was listed. There are 14 members of the genus cornus, dogwood, native to North America, and all of them appear to us to be flowering including Cornus sericea (redosier dogwood).

Therefore, we are assuming that it would indeed be okay to plant the dogwood in the area of the black walnut. If the dogwood does fail to thrive, you can always blame moles or bugs or too much rain or too little rain, just don't blame the researchers or Mr. Smarty Plants. 

From the Native Plant Image Gallery:


Cornus sericea

Cornus sericea

Juglans nigra

Juglans nigra

 

 

 

More Shrubs Questions

Non-fruiting Willamette raspberry plant in Wateford CA
May 23, 2013 - I have a 2 year old Willamette Raspberry plant that has many blooms, bees, great growing conditions, very healthy but has never set one fruit. I know about pruning. Any suggestions? It has been bloomi...
view the full question and answer

Philadelphus ernestii under live oak in Pflugerville TX
April 05, 2010 - Will Philadelphus ernestii thrive in the root zone of live oak, or would the oak inhibit its growth? I'd like to plant it just at the edge of the canopy.
view the full question and answer

Small evergreen shrubs for horse barn in North Carolina
September 26, 2009 - I want to plant some low growing evergreen shrubs in pots in my paddock around my barn. The horses can occasionally be in this are but not for an extended time. I am in NC. Any suggestions?
view the full question and answer

Native plants for full sun in Austin
April 03, 2009 - I am looking for a tough, native TX plant to put in full sun location between the sidewalk and street. I would love for it to flower all summer. There is some irrigation but not much. I don't want ...
view the full question and answer

Natural barrier for sheep in England
July 26, 2008 - Hi I am trying to find a plant that sheep will not eat to use as a natural barrier to keep sheep out of my R/C model flying clubs flying field.It will have to be a couple of feet tall and be a long li...
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.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center