3

I'm in the process of putting together a frame to hold a series of hanging gardens (assorted vegetables and fruits and need to come up with something that will handle the weight load without too much difficulty. We currently have these hanging from an eave of a utility shed, but are not getting good sunlight in that area and I don't think the wood used for the shed is enough to hold the total number of plants anyway.

I've come up with a simple plan that I think will be sufficient for our needs and will be located in an open area of our backyard on cement slab. I'll be building it out of pressure treated 2x4s and decking screws and the unit measures 96 inches high (4 vertical 2x4s) and roughly 48inches square.

Each of the planters weighs between 20-30 lbs depending on dirt load and plant, and hangs from a heavy-duty eye-hook screwed into the frame.

I'm concerned it may be top-heavy, but am assuming that the 2x4s are sufficient to hold the load.

My biggest question is should I be looking at something more like an A-Frame approach or is this 'box' frame sufficient?

Do I need to worry about mounting this in some fashion to the ground?

Here's a mockup:

enter image description here

1
  • 1
    I would avoid using pressure treated wood anywhere that water runoff could contaminate a food source. This why they don't make picnic tables with PT wood on the eating surface.
    – mikes
    Jun 2, 2013 at 23:22

3 Answers 3

5

To add stability you could use 2x6 members for the cross pieces along the bottom. Then cover the bottom with a half of a sheet of plywood. Pour concrete into the box thus formed at the base by the 2x6's and plywood.

You could get by without having to go all the way to full angle braces across the sides (which would get in the way of your hanging plants anyway) by installing some gussets made of thin plywood as shown below:

enter image description here

At a suitable size these would probably come right up to where the first hanging pot wires go.

I see that you have each corner made of just one 2x4. I would encourage you to make the corners out of two 2x4's attached in an L shape in each corner. This will go a long ways toward making the unit a good bit sturdier and will also make the cross bars on two of the sides have a whole lot more wood to bolt into.

enter image description here

I would echo that the proper fasteners for this structure are going to be 1/4" or 5/16" diameter carriage bolts as opposed to screws or nails.

4

I would worry about the structure being top heavy. But I would also worry about it turning into a parallelogram and pancaking. Without any diagonal supports, it's very easy for that structure to pull out a few nails and the corners would then act like hinges until it's flat to the ground. Either way, I'd worry that under a light breeze or someone leaning slightly on the structure, and it would collapse.

An A frame implicitly has the needed diagonal supports and is less likely to tip over with a lower center of gravity. The wider the base, the more stable it will be.

2
  • Agree with diagonals advice. You can can a lot of shear strength from even 1 diagonal in each direction. Jun 2, 2013 at 18:17
  • 1
    +1, although note that you need diagonals in both directions. An A-frame is diagonally braced in one direction by definition, but you'll still need to add diagonals the other way.
    – Hank
    Jun 3, 2013 at 17:19
1

I think you aren't far off. Things I would do different - either notch or bolt the horizontal rails. Add in slats on each level. So on the top have 2-3 pieces crossing and on the level below have 2-3 pieces crossing on the opposite sides. Now you will have a very secure structure but still a little top heavy. So maybe you either anchor is in or you could put a piece of plywood on the bottom and cover it with soil so the base is hidden. I like the overall design though - it looks cool. I just think nailing the horizontals will make it pretty weak.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.