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View Full Version : Raised bed around tree trunk. Will dirt mess with tree?


BrendonTW
03-07-2010, 12:52 AM
Pretty simple. A customer wants me to raise a flower bed about a foot at the base of a large tree (2-3 foot diameter). Will the dirt added about a foot up do any damage to the tree?

StoneFaced
03-07-2010, 01:25 AM
Yea, it will cause the trunk to decay. The bed needs to stay below the crown.

BrendonTW
03-07-2010, 01:29 AM
Ehh crud. I guess there's no way to get around this? The truck has some root "tops" that are above ground which have bark on them as well, so I essentially can't put any dirt around this tree..?

StoneFaced
03-07-2010, 01:43 AM
The tree won't like it, but you might get away w/ doing a very modest raised bed on it. What you will find over the next few years is that the tree will end up filling the bed w/ a lot of hair root. Just try to keep it away from the trunk a bit, because you can also get termites or other insect damage. The one thing you have going, is the size of the tree w/ an enormous root zone, assuming the tree is healthy. If overdone, it may take several years for any stress to show, just make her realize what she is up against...better yet put it in writing, and get her to sign off on it.

Dreams To Designs
03-08-2010, 10:26 AM
Skip the raised bed. Pocket plant perennials between the existing root, use a good organic mulch and surround the roots and perennials. The tree will live and you'll have an additional decorative element.

Kirk

glaciator
03-09-2010, 10:43 AM
I'd have to agree with Dreams. You are asking for trouble. You can amend the soil around the tree roots and add maybe an inch or two of soil, but more than that and you will smother the tree. Tree roots need oxygen which is why they are near the soil surface. Define a nice bed with edging and plant shade loving perennials. They will compete with tree roots which is why amending with an inch or two of soil is the way to go. That way the new perennials have some fresh soil to root into.