SpurTopia's Invention: Self-watering planter box

Self-watering planter box

We invented a self-watering planter box for growing all kinds of vegetable. The box stores around 10 litres of water so no need watering for several days even weeks. More importantly, by up-cycling materials: styro-foam boxes from local fruit and vegie shops and a piece of plastic pipe from kerbside we divert stuff going to land field. Vegetable thrive in these boxes as they have constant wet feed from the bottom encouraging plant roots growing down rather on a surface. It's also water efficient as only water used is by plants - no evaporation or water run off. The planter box retains nutrition during rain while in a garden bed they leach out. Also soil never get bogged and a float indicates amount of remaining water. The self-watering planter boxes are mosquito proof - the float in watering-in pipe and fly mesh from in the overflow hole. These boxes are perfect for balconies and patios also in places where soil is so bad that nothing would grow there. We successfully grow vegetable on a concrete yard in full sun with no shade even during hot summer.
How to make self-watering planter box from recycled materials in 5 minutes? It is so simple, get a styrofoam box and a piece of pipe. We use a broccoli or salmon boxes, 50mm PVC pipe and a wooden skewer.

Step by step manual:

Guts of the box

- Cut the lid to fit in the box by sharp knife.
- Make three holes for pipes in the center line of the lid. Make sure holes are slightly smaller than PVC pipe so the lid does not slide. Use a smaller diameter pipe or the end of a silicone tube, which works well for 50mm PVC pipe, to cut holes.
- Cut a corner of the lid to fit a watering-in pipe.
- Punch randomly holes in the lid by a screw driver.
- Cut three or four pipes (legs) about 10 cm long by a hand saw, the watering-in pipe length to fit box height  about 30cm.
- Screw pipes into holes so they hold firm in the lid. Alternatively create support legs from styrofoam off-cuts, so the lid does not slide down under weight of soil.
- Place lid with pipes down into the box so it creates a raised floor. Add watering-in pipe into a  corner.
- Make a float. Use a styrofoam off-cut and shape it into circle of smaller diameter then pipe. Stick a wooden skewer in it. Slide it into watering-in pipe and cut the top of the skewer at the same level as the watering-in pipe.
- Make a overflow hole into a side of the box at the same level as the raised floor. It's handy to have watering pipe and overflow hole on the same side of box.
Photos step by step to make self-watering box

Self-watering Planter Box schematic

Ready to plant box

Fill in pipes with soil thoroughly then add soil to the top of the box. Soil will act as a wick (by a capillary effect) bringing water up to plants. A float indicates how much water is in the box. The overflow hole in the side of the box allows overflow when watering in or during long rain when the water storage fills up. Punched small holes in the lid provide drainage and an aeration of soil from the bottom. You can paint the box on outside to make it last longer. Ours are without paint and still in good conditions after a year of use.
This is the cheapest (using recycled materials for free), the most effective (10 litres water stored) and  insulated (styrofoam is a great insulation) Self-watering Planter box we know of. We have been using these boxes for a year and successfully growing organic and healthy vegetable such as: capsicums, chillies, tomatoes, eggplants, cucumbers, leeks, onions, garlic, strawberries, beans, lettuce and other leafy vegies and herbs etc.


If we can make it for free you can make it for free.
We also run free hands-on workshops: Make your own self-watering planter box.
For more details see http://spurtopia.blogspot.com.au/p/events-workshops.html
Happy Gardening

Lash veggie during hot summer days

Vegies thrive in self watering planter boxes on a concrete yard