DIY Mobile Planter Box

Learn how to turn an old shipping container into a mobile raised planter box!

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by AdobeStock/Olexandr Kucherov

DIY Garden Projects (Hardie Grant Books, 2016) by Mat Pember and Dillion Seitchik-Reardon is all about fun and practical projects that will transform your backyard into a functioning vegetable garden. Included are step-by-step instructions for 38  projects that will get you out of the house and into the garden! The best part is that these garden projects are made using inexpensive or upcycled materials. This excerpt comes from chapter 2, “Upcycling & Recycling.”

You can purchase this book from the MOTHER EARTH NEWS store: DIY Garden Projects.

Things You’ll Need…

• recycled packing crate
• castors (swiveling wheels)
• 20 x 50 mm (2 inch) bulge head screws
• drill set
• food-safe plastic (builders film)
• timber for bracing (optional)
• old plastic pots
• styrofoam boxes
• weed matting
• staple gun and staples
• 5 – 10 x 30-liter (27-quart) bags of premium organic potting mix (depending on the size of your container)
• your favorite herbs or other plants

People now seem to talk about raised garden beds with an overwhelming belief they will make expert gardeners of them. However, the sad truth remains that if you are a delinquent gardener and kill plants unwittingly, a raised bed won’t stop this happening though it will make it much harder.

A raised garden bed can be anything that is used to elevate the growing level of your garden and it doesn’t have to be built for that purpose. In fact, a number of salvaged items can be used to fulfill the need. This means a treasure hunt and the search for useful things that cost little to no money.

When searching for inspiration, choose from materials that are non-toxic. After all, one of the motivations of growing your own produce is to ensure the food grown is chemical-free and damn tasty, so why compromise that by using a vessel that could leach nasty chemicals?

Practice your haggling well before you are called into action at whatever salvage yard, refuse center or hoarders’ house you stumble across. Our technique is the three-phase strategy – start low, look confused, and don’t say another word. We’ve had mixed success over the years. It’s a bit like fishing – you often don’t even get a bite, but in the right conditions and at the right time, you could be in for a haul.

Remember that traditional raised garden beds are generally built out of durable materials to last and on soft landscapes so that water will drain through the existing soil structure.

Our salvaged or upcycled items – fruit bins, packing crates, wheelbarrows, old bathtubs – are contained and, in some cases, less than durable. They are guided by a different set of rules for preparing them and ensuring they function well.

two men dragging a wooden crate off the back of a white pickup truck

1. First comes the hunt. If you’re anything like us, you will relish the challenge of finding your recycled crate and at a rock bottom price. Without giving too many of our secrets away, look up timber recycling centers or maybe you know an importer. Tiles, car parts, white goods, garden pots, things used to disguise illicit drugs – all sorts of interesting stuff – arrive on boats in nice, big wooden boxes. When scouting, make sure you don’t turn up in an expensive 4×4 (SUV); it will knock you back a step in the haggling process.

man using an electric drill to screw a wheel on to the underside of a wooden crate

2. Because your raised bed is contained, it has the potential to be mobile, and castors will help with this. However, be aware that a large box filled with wet soil is really, really, really heavy and will not only require heavy-duty castors but also a smooth rolling surface. Turn the container upside down and attach each castor to each corner using hex screws. It’s best to drill a leader hole before attaching each screw, and an impact drill will make the job a pleasure.

man holding a blue electric drill to the inside of a wooden crate

3. The next thing to consider is drainage. Even though the recycled crates you use won’t be watertight, they won’t drain particularly well, so be generous in adding drainage holes using the power drill and some 10-20 mm (1/2-3/4 inch) drill bits. A couple of tiny holes at the base generally won’t be sufficient – give water freedom and help it out.

wooden crate on wheels next to a drain in concrete

4. Be aware that there will be drainage runoff, so be mindful of where the water will run when placing your box. Locate it close to a drainage point or near soft landscaping (grass, for example). This will mean your space will be left clean and dry rather than a slippery, dirty mess.

man stapling black plastic sheet on the inside of a wooden crate

5. Unlike your traditional raised bed that is built to last (made out of lovely dense timber or stone), your recycled unit was probably not designed to hold large quantities of wet soil. When you can, help protect the wood from premature rotting by lining the box with food-safe plastic. Cover and staple the sides because they will make contact with wet soil but don’t line the base and make it watertight again!

man using an electric drill to screw a cross bar to the inside of a wooden crate

6. With a deep unit, decide whether to entirely fill it with soil. If you are planting a fruit tree, this may be necessary, in which case it is best to BRACE your crate. Do this by attaching two timber panels on the inside wall of the crate and then joining them with a bracing timber. This way the force that the soil and water put on the unit is largely diminished.

man placing styrofoam box over top of plastic pots inside of a wooden crate

7. Most edibles, however, only require 12 inches of soil, and reducing the volume will lessen the stress on the container. You can build a false bottom using old plastic pots, covered over with styrofoam boxes for extra strength. This will elevate the soil height. First, build your pots up. Once you are satisfied with the level of the pots, place styrofoam boxes upside down over the top, which will create a relatively even, flat base.

man stapling weed matting across a wooden crate

8. Now, lay weed matting over the top and staple it into the timber so that the soil does not fall through.

man dumping a bag of organic potting soil in to a wooden crate

9. Fill with good-quality organic potting mix. Don’t be stingy at this point. In small spaces, better quality soil makes all the difference.

man planting an herb in a wooden crate filled with potting soil

10. Plant out with seasonal produce.

two men standing on a wooden crate with produce planted in it on wheels

Your container will now be a good-looking, durable, and mobile food-growing machine, ready to be put to use.

More from DIY Garden Projects:

The Ultimate Tomato Trellis

book cover with garden planter, person holding strawberries, family planting in a plastic tub, and a wooden building on it.

Reprinted with permission from DIY Garden Projects by Mat Pember and Dillon Seitchik-Reardon and published by Hardie Grant, 2015. Photos by John Laurie. Buy this book from our store: DIY Garden Projects.

  • Updated on Nov 1, 2021
  • Originally Published on Jul 1, 2020
Tagged with: diy, garden, planter, recycle