Hydroponics and indoor gardening are two popular methods of growing plants in controlled environments. Indoor gardening is a little more broad-encompassing, utilizing methods such as window-sill growing and greenhouses where soil is still used. Hydroponics refers to methods that do not use soil. It's a method of growing plants specifically using nutrient solutions in a water-based reservoir system that cycles. Growing mediums like perlite and clay pebbles are often used in place of the soil, where plant roots can easily sift through into the water flow.
The first published records of growing plants without soil began around the mid 1600s, but only really started to evolve in the 1930s. This brief history is just to show hydroponics is still a relatively young practice compared to things like blacksmithing or homebrewing.
Different Hydroponic Methods
There are a handful of popular methods for practicing hydroponics, all which have different uses and benefits for specific plants. Our hydroponics and indoor gardening table focuses on one of the most widely used methods, deep water culture.
Deep Water Culture: Plant roots are suspended in a nutrient rich solution of oxygenated water via air pumps and stones. It's an affordable and effective method that allows plants to grow much quicker than other methods due to the large amounts of oxygen being directed into the roots. There are slight variations of the DWC method, such as top-feeding where the solution is pumped from the reservoir up to the roots, allowing for greater growth during the first few weeks (because the roots get immediate access to the water).
Static Solution Culture: Plants are placed in containers of nutrient solution. Containers can range from mason jars to plastic buckets and tubs. The solution is normally aerated a bit but can also be un-aerated. The solution is then changed out on a specific feeding schedule. This is another cost-effective way to approach hydroponics.
Continuous Flow Solution Culture: Unlike the static method the nutrient solution will always flow through the roots (as opposed to remaining static). This method is best suited for a large group of plants where a reservoir contains the supply of nutrients and can easily be altered to impact all plants.
Aeroponics: A more recently developed method (developed in 1983), aeroponics involves putting roots in a continuously/discontinuously environment saturated with a mist/aerosol of nutrient solution. The plants grow with their roots hanging in an air chamber. This method allows plants to receive fantastic aeration and favor well with propagation, seed germination, seed potato production, tomato production, leaf crops, and micro-greens.
Ebb and Flow: A tray filled with a growing medium is placed above a reservoir of nutrient solution and a timed pump fills the tray with nutrient solution, which drains back down into the reservoir. This method helps keep the growing medium stimulated with nutrients and air.
More: Additional methods include rotary cultivation, run-to-waste systems, fogponics, and passive sub-irrigation.
Nutrients & pH
There are hundreds upon hundred of different nutrients and solutions which empower different plants to grow larger, flower quicker, fight diseases, and more. We've put together a guide to plant food and soil supplements which reviews over a dozen of the best options on the market for hydroponics and indoor gardening.
Growing Mediums for Hydroponics
Since hydroponic methods do use soil there are a handful of popular options which include:
As you can see there are many interesting alternatives to soil. Selecting the right medium largely depends on which hydroponic method you are going to use. For the sake of a beginner who uses the DWC method, clay pebbles are often the medium of choice.
Deciding What to Grow
While there are many plant options, one of the most obvious and widely selected home-user option is cannabis. You'll have to use your best discretion and check your state/country laws if that's what you decide on. There are also very affordable (~$100) methods for growing cannabis and other plants such as the SpaceBucket method. But the options are really limitless; from celery, radishes, and eggplants to potatoes, leeks, rhubarb, and squash, we really can grow whatever our heart desires. Our hydroponics equipment table is designed for heavily controlled growing environments where factors such as smells and lighting are important factors as well. But you can easily tweak the equipment you need to best suit the plants you'd like to grow.
There are many other nuances to hydroponics which will be added to this beginner guide in the near future. If you have anything you'd like to add or change in this guide feel free to contact me.