First off, hello everyone – rather new poster here, but I have been lurking a while. I will be a first homeowner in a matter of a month, and I have several DIY projects I will be trying over the next few years. I am really good at reading/following directions and conceptualizing things, but just don’t have a lot of experience actually DOING it. So, I will be posting a few of my projects on these forums and hope some of you with more experience can point out some possible problems or just another viewpoint and help me out a bit.

Note: I am putting this project in the Gardening section because I haven’t found a specific “Landscaping” section and many of my concerns revolve around the health of the tree.

Project #1
Circular decorative block planter box around medium-sized maple in front yard.

Objective: Increase curb appeal of house and provide an area to plant annuals or possible perennials and at the same time possibly preventing weed growth around the tree.

Plan: I plan to install a circular planter box around a medium-sized Silver Maple in the front yard to replace a flimsy, rotten wood one. I want the planter to raise about 1 foot above the surface of the lawn. I plan to fill the inside of the planter with good dirt with a covering of either cedar or cypress mulch for decorative purposes. I am also exploring the options of weed-prevention measures. Eventually the goal is to plant a few annuals or perennials around the tree in this box.

Method:
I will start by visually locating the point where the root crown of the tree stops (where the soil stops being pushed up by the roots near the trunk of the tree). I will then make the planter box farther out than that point to allow for growth and so I don’t damage any of the main roots when I dig.

After I measure the radius I want (the bricks will be included in this distance), I will cut a string of that length and use marking paint and the string to draw a circle around the tree of approximately equal distance. I will then use a trenching shovel and cut the sod around the circle and remove it up to the base of the tree. I will then dig a small trench around the circumference of the circle about the width and depth of one brick. I will use a level to make sure the ground is relatively level in this trench and even it up until it’s close.

I will then lay my first circle of bricks so that they are even with or slightly above ground level. I will continue to lay additional circles of bricks on top of this first one, staggering the brick junctions, until the box is to the height I am looking for. I will then fill the box up with fill dirt about 3/4 the height and lay down my weed countermeasures*.

I will fill the rest of the box up with cypress or cedar mulch up to just under the rim of the box so that it will be held in better when it gets very windy or rainy.

Questions:
1. I don’t want to have to cut bricks and have a half-brick in my circle somewhere. I was thinking of figuring out the circumference I want for the box and making sure it is equally divisible by the lengths of the parts of the bricks that will connect (they are slightly curved bricks) – will this work or is there another way?

2. I don’t wish to harm the tree by doing this project – will filling in dirt around the trunk by about half a foot damage the trunk and endanger the tree? If it will damage the trunk by having dirt in direct contact with it I was thinking about putting a small, corrugated pipe around the trunk before I backfill to keep the dirt off of the trunk and allow it to breathe a bit – would this be preferable or does it matter?

3. I was thinking of methods to prevent weeds in the bed and there are several problems – if I use Tyvex or plastic sheeting, it will prevent water from getting down to the soil and to the roots of the tree and whatever plants I plant in the box. This is somewhat undesirable – I want the water and air to be able to penetrate downwards but also prevent weeds from growing. Is there any other solution of a permeable membrane that would allow water and air to pass but would inhibit weed growth? I know the mulch will go quite a ways to preventing weeds but if I can find a material that does what I am looking for, I would like to use it.

I would welcome any suggestions or tips.
Thanks in advance.

 

Welcome to the forum. There is no limit to the number of questions that you can post.

It seems to me that you have thought through this project more than most.

Adding or removing more than one inch of soil per year to the ground around a tree out to the edge of the canopy is risky. The deleterious effects may not manifest themselves for a few years, at which time the death of the tree is inevitable. This is why existing trees die at new houses in a few years - adding or removing soil or severely compacting the soil. So many of the feeder roots are at the edge of the canopy.

You can add mulch without the same ill effects.

Landscape fabric is the preferred choice for barrier weed control. If blocks the growth from beneath while allowing air and water to move through the fabric.

Calculating the layout of the bricks is a good idea. You could run the numbers, then set them on the grass in the approximate location and adjust them to get the rough area, then mark it. When you are laying them, you can adjust the positioning as you go to have them come out even.

The mulch will decompose over time, but will not adversely affect the tree. When you are ready to plant in the mulch bed, dig a spot down to the soil over the landscape fabric, slit the landscape fabric, fold it back for a woody plant such as an azalea or such, and add enough soil in the spot to provide for the plant. Build a mound for the plant to live in. These spot additions of soil should not bother the tree. You won't need to slit the fabric for annuals.

Hope this helps.

 

Thanks for the reply. There is already a old, rotten, wooden planter box around the tree that I will be removing when I put the new one on. The old one looks like it has been there a number of years as the boards look somewhat decayed. Here are a couple new plans then - let me know if these should be OK.

Remove the wooden boards from the old planter box and make the new stone one roughly the same distance out (only round instead of square) and near to the same height with a couple inches room for mulch and a small lip on the top. Refrain from disturbing as much soil currently around the base of the tree as possible when building the stone wall. When completed, put down a sheet of landscaping fabric over the soil and then fill the box up with mulch. When and if we decide to plant things in the box, I will dig down through the mulch to the fabric, cut out an area for the plant and then plant it in the original soil around the tree.

Couple other questions - I have been looking at how to lay bricks and they suggest using crushed rock/sand beneath the first layer of bricks. Since I am doing this planter near the roots of the tree I don't want to dig down that far and risk hitting a main root. Would you suggest leaving out the rocks/sand and just laying the bricks on bare earth, or would you put a small layer (like maybe an inch) of sand under the bottom layer of bricks?

Also, is there any detriment to planting things at the base of the tree in terms of other plants stealing water and nutrients and weakening the tree? Are there certain species we should particularly avoid?

Thanks in advance.

 

Hi thevolcanogod

Fist off let me explain a little to you about DIY. You have found the most unique gathering of people like yourself, you may ever find online.

We have Moderators who have hands on knowledge of their subjects, working their special forums. However it is our members, who make this all work so well. For instance if you have a question on Bricks & morter you can place a question in Masonery & Garden. 2 bases covered

In fact use as many forums as you need, & sometimes the Moderator may move your post to a forum, more suited to the question. Lucky move in many cases.

Also I want to call your attention to the Stickys & search engine on every forum, found at the bottom of each Forum. You see how each post moves down the list. To move it back up, just use the reply button to ask if there are any new ideas, & up your post moves into the active area again.

Last but not least, the internet is endless & I consider myself a good searcher. However I have been given links, like we have in the stickys, that have given me info, I may never have found by myself.

If you need help in any forum just ask the MOD, they will save you a lot of time, finding what or who, you need for help.

Welcome aboard

 

Digging around the tree to install the brick won't be a problem, if the damage to the roots is kept to a minimum. The majority of the feeder roots are near the edge of the canopy of the tree. Your plan sounds good to me.

Laying the bricks on the soil or on a bed of sand sounds good. The sand should enable you to level the bricks as you lay them. It will help reduce movement of the bricks with the soil. If you are going to lay them dry, that is, without any mortar, they will shift around as the soil moves. For instance, frost heave. There is a brick-like product that is laid dry. It has a lip on it to offset each row, so that the backfill won't cause the wall to fall. I have laid regular bricks dry with a bit of an offset in the wall and had them hold the fill.

Actually, whatever is planted under the tree will probably come in second in the competition for water and nutrients. A tree is generally so large compared to everything underneath it that it wins the competition. Most of the feeding activity for the tree will be near the canopy's edge. You can plant most anything under a tree. Of course, some will do better than others because of the shading. I would refrain from planting vines or anything that will climb onto the tree itself. These things tend to harbor moisture on the tree where it ordinarily doesn't have constant moisture. I believe that this will contribute to the deterioration of the tree. Under a tree is often a good place for colorful annuals, such as: impatiens.

Hope this helps.