Introduction: Modular Free-Standing Planter Box Yard Fence / Baby Gate

About: Architect, Urban Designer, all-round tinkerer of odds and ends. Small solutions for big city living. Dreaming of lands faraway where garages are big enough to build a workshop in, or lakes are there for taking…

Hey Instructables!

Here's an all-new concept I came up with for making a free-standing yard fence with a planter box, made out of simple materials and hand-held tools. This is great for keeping pets and toddlers safe, without committing to a permanent fence. Great for renters, or when you know you only need a fence for a few years and don't want to drill holes into your terrace or deck.

This design is modular, so it is easily adaptable to any size or length required. You could just make a single planter to block a path, or a whole row of these as a yard fence.

This is my entry into the 'Safe & Secure Challenge'. I did this design over a year ago, and I don't have any photos of the build, so I've done some SketchUp diagrams to illustrate the step-by-step. I'll give indicative dimensions, but you'd have to adjust to fit the size of the planter boxes you can get.

Step 1: The 'BEFORE'

My driveway (if you can call something barely a few inches longer than my hatchback car a 'driveway') backs up right to my side terrace. I've always worried that my wife'll back the car right into those concrete steps one day, but that's a whole different instructable.

Ever since my kid started to crawl I was also terrified that one day he might decide to run out into our driveway as someone is backing into the lot.

So I set to work designing a free-standing yard fence that would be baby-proof, temporary (no holes in my tiled floor!), and with a gate that we can open easily on a daily basis. Oh, and it had to be aesthetically pleasing. I'm a card-carrying modernist through and through, so no picket fences or unresolved corners are allowed in my designs!

Step 2: And the 'AFTER'

After a few design iterations, here's the SketchUp of my final design: a see-through acrylic and timber fence that is weighted down by planter boxes at the base. The two centre panels are hinged to create the yard gate, hanging off the planter modules.

Step 3: Materials

Early versions of my design included all sorts of planter constructions, some using plastic planter boxes that were completely enclosed in timber screens on all sides. These were far too complicated and expensive for the non-permanent use I had in mind.

There's usually an 'aha' moment when it all comes together as a simple elegant solution. The 'aha' moment for this project was when I found the IKEA Sockerbit plastic storage boxes that have a subtle horizontal design on them. Kinda like horizontal siding. These passed my aesthetic test: nice enough to be left exposed as an intentional part of the design. Bonus that they are pretty inexpensive.

Materials List:

  1. IKEA Sockerbit plastic storage boxes (see photo.) Dimensions 38x51x30 cm
  2. 1x3" timbers for the main module frame
  3. 1x2" timbers for the feet and acrylic panel frames
  4. 3mm clear acrylic (perspex)
  5. Nails for attaching the acrylic (I would use stainless steel screws if I could do-over)
  6. Stainless steel screws for connecting the timbers
  7. Wood filler
  8. Outdoor paint
  9. Geotextile fabric & Drainage Cells to line the planter box (see photo. Also called 'Versicell' and other trade names)
  10. Large pebbles or rocks to weight down the planter
  11. Appropriate soil mix for your plants
  12. Plants

Tools:

  1. Mitre Saw/Chop Saw (or substitute jig saws or hand saws)
  2. Pocket Hole jig & drill bit for corner joinery (or substitute brad nails, exposed screws, dowels, or any other fancy joinery you prefer)
  3. Circular Saw for the acrylic (or substitute a jig saw and lots of patience)
  4. Drill
  5. Hammer
  6. Router to round over edges (optional)

Step 4: Build Acrylic Panels With Timber Frames

I wanted to build a fence 80cm high, which is pretty standard for baby gates.

The planter box is 30cm high and 50cm wide (long), so I made a panel 50cm x 50cm high to sit just above the planter box.

This panel is just 4 timbers (1x2") joined together with pocket holes at the corners to form a square. The pocketholes are drilled in the undersides of the horizontal members, so that they are not visible in the final fence.

Optional: Round-over the edges with a trim-router and a round-over bit. I chose to only round the inner edges of the frame, to keep the outer frame edges nice and visually crisp. (Yes that whole minimalist modernist thing again!)

Paint the frame with outdoor black paint, before attaching the acrylic.

The acrylic sheet is cut to size and attached to the back of the frame with small stainless steel screws (I used nails, and they rust!). I cut the acrylic slightly smaller than the frame, to allow for any potential misalignment due to warping of the frame. Remember to sand the cut edges of the acrylic so that it's not sharp.

Tip 1: You need to use pan-head screws and pre-drill holes in the acrylic sheet, otherwise you will crack the acrylic.

Tip 2: Keep the protective paper on the acrylic until the end!

Step 5: Build Timber Frame Around Planter Box

The main verticals of the fence module are made out of 1x3" timbers. These are the 'fence posts', if you will.

Basically I cut 2 verticals at 70cm and a horizontal base at 50cm and connected them into a U-shape with pocketholes at the bottom. Yes, this is intentionally 10cm shorter than the 80cm fence. This leaves a nice gap between each rectangular fence panel at the top.

The feet of the planter are made out of 1x2" timbers, cut at 30cm to match the width of the planter box. See the photos for more details. These were just screwed to the bottom piece of the U-frame with countersunk screws, to make a base for the planter box to sit on.

This U-frame is screwed into the sides of the planter box with 2 1/2" countersunk screws, with spacer blocks on the inside and outside of the planter box for a nice tight fit. (See the diagram)

Once the planter is filled with soil, it anchors this whole set-up firmly.

Finally the 50x50cm panel is screwed to the vertical fence posts with countersunk screws, to complete one free-standing planter module.

Congratulations, one module done!

Step 6: But Is It STABLE? (Some Boring Calculations)

Okay so you may be wondering how stable this thing is. Last thing you want is to call something 'safe and secure' only to have it fail you.

So at the design stage I did the following calculations: The bin is 38x51x30cm, or about 58 litres when full.

From the USDA website: "Bulk density is dependent on soil organic matter, soil texture, the density of soil mineral (sand, silt, and clay) and their packing arrangement. As a rule of thumb, most rocks have a density of 2.65 g/cm3 so ideally, a silt loam soil has 50% pore space and a bulk density of 1.33 g/cm3."

So, assuming 1/3 rock and 2/3 soil, the average density is about 1.77 g/cm3 or 1.77 kg/litre. So the overall weight of this planter base is 1.77 x 58 = 102.66 kg

Given a base of 38cm, vs a height of 80cm, this planter should be able to withstand a lateral tipping force of about 24kg applied at the top.

My kid is only 15 kg at the moment, so there is a pretty good factor of safety. Furthermore, the planter base itself prevents the kid from getting too close to the fence anyhow. Finally, this is really just a deterrent and a physical reminder for the kid to not run onto the driveway. It's still our responsibility as parents to teach him basic safety and keep an eye out for grave danger!

Summary: This has been tried and tested for over a year and it works. The main risk of failure is us adults forgetting to lock the darn thing!

Step 7: Filling the Planter Box

I'm no expert in plants, but what I do know is this:

  • Make sure you drill holes in the bottom of the planter box for drainage.
  • Line the bottom of the planter box with a plastic drainage cell layer to allow for good drainage at the bottom.
  • Cover that with geo-textile fabric (non-woven synthetic fabric) to prevent soil from washing out the bottom
  • Line the bottom of the planter with heavy rocks and pebbles for stability and drainage
  • Add on appropriate soil for your desired plants. (I used a mixture of compost, burnt soil, and vermiculite granules which help in drainage)
  • Add plants
  • Add more compost around the plants
  • Water them and give them some TLC

This advice would probably vary wildly depending on your climate and your plants.

Step 8: Connect Side Panels to Planter Unit

In theory, you could just place a whole lot of those planter modules side by side to make a continuous planter-fence. But in my case I realised that I could cantilever a smaller acrylic panel to either side of the planter module like wings. This means I can use fewer planters over a length of fencing.

These side panels were made at 70cm tall by approx 40cm wide. These are mounted with the tops level with the adjacent panels, at 80cm height. Again, use countersunk screws for this. This leaves a 10cm gap at the base, to allow for water flow etc.

Step 9: Making a Swing Gate

For my set-up, I used the two planter modules as 'gate posts' to hang off two swinging gates. These were just hinged on with regular door hinges, and locked from the outside with a simple flip latch from the hardware store.

Step 10: Add Modules to Get Your Overall Length

That's about it! There are three basic modules:

  • Planter box section
  • Intermediate panel
  • Gate panel.

These can be combined endlessly to create a long fence in whatever configuration you need. Just make sure you have a planter box every 2-3 panels to anchor it all securely. The images show a possible alternating arrangement of planter/intermediate/planter/intermediate as a continuous fence.

Step 11: Finished Yard Fence

And that's it! A couple more saturated green photos of my tropical side yard in the middle of January (to make all you temperate climate folks jealous), to show off the final product.

I've had this for over a year now, and it's been very effective in every aspect. The planters give us a lovely pop of greenery at our doorstep as we come home, and the transparent fence with black frames blends right in with the architecture of our house. And most importantly, it's kept my kid safe as he plays in the side yard!

Please do vote for me in the 'Safe & Secure' contest if you liked this! Thanks and stay safe.

Step 12:

Safe and Secure Challenge

Second Prize in the
Safe and Secure Challenge