Return to the Plants for Difficult Places Forum | Post a Follow-Up

 o
arborvitae allelopathic?

Posted by Cassiope 03/WI (My Page) on
Sun, Dec 5, 04 at 11:17

Hi,
I posted my problem with native plants, and many people offered great suggestions - which I fully appreciate - BUT - I've spent 8 years tackling this problem and want to do it absolutely right this time.
A section of my garden is framed by 2 tall arborvitae on the north side and a Black Hills spruce on the west side. For 8 years I've been unable to grow anything here successfully. The soil is sandy (I do keep amending it with compost). Do either of these species inhibit other plants somehow? Whenever I prepare the soil for something new, I dig up lots of shallow roots. Since it's at the back of the border I need something tall. Thank you!


Follow-Up Postings:

 o
RE: arborvitae allelopathic?

  • Posted by Rosa 4-ish (My Page) on
    Sat, Dec 18, 04 at 12:48

This site lists Thuja plicata as having leaf litter that is slightly allelopathic but no other species are mentioned.
http://plone.urbanforestrysouth.org/Resources/Library/Citation.2004-07-15.3616/file_name/

However, this one states that there is no documented evidence of this occurring:
http://www.puyallup.wsu.edu/~Linda Chalker-Scott/Horticultural Myths_files/Myths/Allelopathic wood chips.pdf

I cant find anything more specific but would suspect that a combination of shade, and water competition from those abundant, strong, fine roots near the surface is more likely the problem.

Sorry, but I dont have any plant suggestions for you.


 o
RE: arborvitae allelopathic?

Thanks Rosa-
I think you're right. I find it very frustrating though, this was to be my beautiful border garden with the conifers acting as a landscape foil. As it is, it's my least attractive bed. I think I need to find a plant that also has competitive roots, or else one that can suffer through dry conditions.


 o
RE: arborvitae allelopathic?

  • Posted by Rosa 4-ish (My Page) on
    Mon, Dec 20, 04 at 16:34

Dry shade is sure a tough one. Maybe others in your area have some experience and some good recommendations....
You might try posting for plant ideas on the native plants, perennials and shade gardens forum.
Good luck!!


 o
RE: arborvitae allelopathic?

I do believe that arborvitae litter is not conducive to other plants in some way. I have found that salvia greggi seems to grow happily with it for some reason.


 o
RE: arborvitae allelopathic?

Brenda-
Salvia g. sounds perfect except for it's hardiness. Do you know of a plant with similar tolerances but also cold hardy (I'm in zone3/4)?

Maybe if I do annual salvias?


 o
RE: arborvitae allelopathic?

Maybe an agastache? I love Agastache rupestris, easy from seed, and it comes from the Rocky Mountains, so should take cold.


 o
RE: arborvitae allelopathic?

Great idea!
I don't know if anyone else gets frustrated with the seasons - I wish I could try many plants in one season for this spot, so I'd be sure to have success.

I just checked in my High Country Gardens catalogue. They have A. rupestris - it is very pretty. I love their stuff, but have been hesitant to buy many of their plants because of the difference in rainfall and humidity between Wisconsin and New Mexico.

I do love Agastache. I think I will give it a go. Another problem I have is my garden gets too crowded. I think I need to dig up more lawn this year! (so far I have New Jersey Tea, Baptista australis, and now A. ruprestris slated for that spot)


 o
RE: arborvitae allelopathic?

USDA actaully lists arborvitae as not-allelopathic, but their database is not perfect. Too bad I'm out of the A.rupestris seeds for this year. I have some other Agastaches, but doubt they're hardy for you. Keep me in mind for trading next season!


 o
RE: arborvitae allelopathic?

Thanks Brenda for the info. My soil is the opposite of yours - very sandy which in combination with competition with arborvitae roots might be the problem.

It'd be fun to trade seeds with you. I generally don't collect seeds from my plants - I usually buy all my seeds. But if you're interested, I have alpine plants, native (mostly shade) plants, and a few sun loving natives. (I'm guessing only seeds exchanges are possible) Unfortunately our yard is small - so I'm limited. So next season - I'll look you up!


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!


Return to the Plants for Difficult Places Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.


Learn more about in-text links on this page here