Building Wooden Tomato Cages

Regular readers (they exist?) of this blog will know that I have been growing tomatoes for a while. The Season Red tomato cultivar that I have been growing is supposed to be a determinate type, which means that it should reach a certain size and the stop growing. That and the fact that I am growing it in containers lead me to believe that they would not require much more than a single stake to support.

Instead I found that they grew much larger than was practical to support with stakes. This is particularly true if you want to keep the container movable which means that you cannot place the stakes into the ground around the container. I realised that I needed some sort of more serious support structure for my tomatoes.

I have often though of building cages that look something like this, but the need to weld has put me off. Even if I could get hold of welder, I’d probably kill myself. I’m a klutz… So I decided to think of something that could be built fairly simply and cheaply using only basic tools. This is what I came up with:

Completed wooden tomato cage

Advantages and disadvantages


  • looks natural
  • doesn’t require welding
  • can be made by idiots


  • Less robust
  • more expensive?
  • less durable?


  • 4x 1.8m long, 16mm diameter pine dowels
  • 4x 900mm long 8mm diameter pine dowels
  • 0.9m and 1.8m long 25x40mm pine planks
    • Cut into 4 500mm long sections and 4 40x40mm blocks. There will be some leftover.
  • 8 4x40mm wood screws
  • Wood glue for future repairs :)


  • Electric drill
    • 16 mm wood drill bit
    • 8 mm drill bit
    • 3 mm drill bit
  • Hacksaw/steaknife
  • pencil


Base construction

The base supports the whole structure from the ground up. The trellis will be supported by inserting the 16mm dowels into the 16mm holes that will be drilled into the base.

  • Align the 500mm pieces of plank such that they form a square, with the ends overlapping so that the corners form double-height regions.
  • Starting at a corner
    • Ensure that the two planks meet flush, and at right angles.
    • drill two diagonally opposed 3mm holes, penetrating both pieces of plank. Ensure that you are not to close to the edge of the top or bottom planks, but leave enough space for a 16mm hole through both.
    • Attach the two planks using screws through the 3mm holes.
    • Repeat for the other corners.
  • Drill a 16mm hole at each corner. The holes should go through the top plank, and about 2/3 down the bottom plank. Should look something like this

Top side of base
Bottom side of base

Top support construction

  • Drill a 16mm hole about half way through 4 of the 40x40mm plank blocks.
  • Drill an 8mm hole on two sides of each block such that all four can be connected to form a square.
  • Connect the blocks using the 8mm dowels to form a square.

Closeup of top-support connecting blocks
Assembled top support

Marking the posts

The trellis will be constructed by winding wire around the four support posts. To do this we will mark the four posts in sequence such that each quarter rotation results in the trellis being 20cm higher. To do this

  • Lay the four support posts alongside each other on the floor.
  • Alternately mark each of the posts every 20cm, starting again at the first post once you reach the fourth.
Marked posts

The posts are marked every 20cm such that every quarter rotation around the structure results in the wire being 20cm higher.

Assemble all the wooden bits

  • Place the base on the ground with the 16mm holes pointing up
  • Stick the support posts firmly into the 16mm holes. You might wrap paper around the ends if the don’t fit snugly into the holes
  • Connect the four posts to the top support by placing the posts into the 16mm holes in the blocks. This will keep the top from collapsing.
Cage complete except for wire

Winding the trellis

  • If the plant you are trelissing is already somewhat grown, you might want to place it inside the cage before starting to wind the trellis.
  • Using the hacksaw (or knife) make notches in the posts at the pencil marks. Angle the notches slightly down when sawing. This is to keep the trellis wire from slipping out.
  • Tie the construction wire around the first post.
  • Working around the support posts, put the wire into the gaps. Mind to keep the wire under a bit of tension so that it can support the weight of the plant that will one day lean on it.
  • Tie around the top support structure.
Sawing support notches for the wire

Saw slightly downwards, at a 45 degree angle to the base

And there you go, a cage to contain your tomatoes, or other climbing plants.


So far my cages have held up reasonably well. They look a bit distored now due to the tomatoes growing somewhat asymmetrical. They also blew over in one of our Cape windstorms, resulting in some of the top connecting blocks breaking. This is where the woodglue came in :) I have since put some gravel in bowls on the bottom frame to keep the cage upright in the wind. Something that I may also want to try in the future is the tormato, a trellis constructed using only plastic pipes!


  1. Le Roux
    March 16th, 2011 at 10:16AM


Comments go here.

(will not be published)
Remember Me
Subscribe to Updates