Making your own hydroponics system from household items is a great afternoon project that not only teaches kids where food comes from but also shows them the value of recycling. You don’t need to invest a lot of money to have a hydroponic garden on your deck, patio or in your house. You probably already have most, if not all, of what you need to get started growing today.
A hydroponic reservoir holds the liquid nutrient solution that is at the heart of every hydroponic system. The size of the reservoir depends on the overall size and type of the hydroponic system. Common household items that make good reservoirs include 2-liter soda bottles, plastic storage bins, foam ice chests, buckets and children’s wading pools. Containers should never have been used for anything toxic such as herbicide or paint, they must hold water and it’s best if they are opaque so no light gets into them to discourage the growth of algae.
Some types of hydroponic systems utilize net pots set into a larger container to hold individual plants. While these are easy to find and affordable to buy, making your own gives you complete control over the size and shape of the pots. Almost any plastic or foam cup or food container – a coffee cup, yogurt package or milk jug -- works well once you poke the bottom and lower sides full of holes using a pencil or a soldering iron. Be careful about burns and don’t inhale the fumes if you use a soldering iron; keep the soldering iron out of the reach of children.
The medium in a hydroponic system takes the place of soil when it comes to giving the plant support, but it does not provide any nutrients. Almost anything that allows water to flow through it will work, including sand and pea gravel. Smaller plants grow when supported by cotton balls or toothpicks. Perlite or sawdust also work well and hold the water longer than gravel. When floating a piece of polyurethane foam on top of the reservoir, poke holes in it just large enough to hold your seedlings with the leaves above and the roots dangling below and you won’t need a medium at all.
The main ingredient for a homemade nutrient solution is a good, all-purpose fertilizer that is completely water-soluble, such as what you might use on your houseplants or flower garden. Be sure it includes both micronutrients and macronutrients or your hydroponic plants won’t survive long. You’ll also need Epsom salts, the same kind you keep in your medicine cabinet. Mix 2 teaspoons of fertilizer and one teaspoon of Epsom salts in each gallon of water you use in your system to provide the nutrients your hydroponic plants require. If you are pregnant, wear gloves and a mask whenever you work with fertilizers.