Growing vegetable crops without soil is practiced around the world from household systems up to large commercial vertical farms. Meet Vilma and Dave Anderson, my friends and fellow vegetable gardeners, who introduced me to their successful, home-made hydroponics set-up. Water and nutrients are not wasted here. They are collected and recirculated in their “ebb & flow” system. The plant growth and harvests are quite impressive for a range of crops. I posed a few questions to Dave recently to try and capture their story and adventure in hydroponics.
What got you started and how long have you been doing it?
I had not even heard about hydroponics until we took a trip to Disney World’s EPCOT in 2012 where they have an extensive hydroponics facility where they do all sort of amazing things, not just with hydroponics but with aquaponics, aeroponics, etc. I really recommend their tour of the facility the next time you find yourself at EPCOT. My wife and I returned home and decided to give it a try. YouTube had a few videos on setups that people had tried at home and we used a modified version of what we saw there to set up three tomato plants in an ebb and flow type setup that we placed on our patio. We were stunned by how successfully the tomatoes grew and we were hooked. That experience from three plants has grown to 30 plants of vegetables of all sorts including tomatoes, peppers, eggplants, cucumbers, squash, and tomatillos.
Did you have previous gardening experience?
I have been growing vegetables for many years both here and in Tucson where we lived for 16 years. My garden here was pretty small, about 300 square feet, and not particularly sunny but I managed to grow tomatoes, peppers, and squash of various types with more or less success.
What are the differences between indoor and outdoor hydroponic gardening?
I don’t do any indoor hydroponics except growing lettuce which does very well in our cool basement. The reason I do outdoor hydroponics is mainly because I don’t have a greenhouse or the space to have a greenhouse so I have set up hydroponic units all over my backyard wherever I can make them fit. Our original vegetable garden now has 16 pepper plants all running off a single feed tank. Other units are setup on my patio and along the border of my backyard. Vegetable plants get pretty large so doing it inside the house would be impractical although Vilma at one time wanted us to turn a spare bedroom into a “greenhouse” and grow tomatoes year round. Still thinking about that. Of course, the main reason for doing hydroponics outdoors is the same for any gardener, the sun! Indoor hydroponics not done in a greenhouse needs artificial lighting. Many commercial growers worldwide do just that and have highly controlled environments where plants can grow amazingly well.
What do you feel are the main advantages to hydroponic gardening?
The principal advantage is that you are not using soil as the source of water and nutrients for the plants, you are literally pumping them directly to the plant in the most efficient way possible. Water use alone is cut by up to 90%, the only water you use is what the plant actually uses. Now, that’s not a big consideration here given our climate but it’s a real concern in many parts of the world. I just like the idea of minimal water usage. Also, you are not dependent on the weather to water the plants. Likewise, you are giving the plants exactly the right amount of nutrients with no waste getting lost in the soil. Yields of plants grown hydroponically can be much greater than those grown in soil. Some take issue with the fact that the nutrients come from “chemicals”, i.e., inorganic salts but I personally don’t see much difference between dumping fertilizer on your soil-grown vegetables or mixing it with water and applying it directly to the roots hydroponically. Since there is no soil you also don’t have any associated soil-borne pests and diseases to contend with, although plenty of air-borne ones! Also, there is no weeding to do!
What are some difficulties you’ve encountered?
One difficulty is that the hydroponic setup is somewhat more complicated and expensive than planting a garden in soil, although that has its own set of challenges. Instead of roots, soil composition, soil nutrient content, etc., you have issues of a different kind with hydroponics since you need a source of power for the pump, a water source if you want the system continuously filled, and the containers and hardware that make up the system. Once a system is built, however, it can be used over many years with any variety of plant. In hydroponic systems, very large plants can be grown in small containers but you still need a method of supporting the plants as they grow. I think this is one of the biggest challenges in hydroponics and one that commercial growers spend a lot of effort on. Some sort of support structure must be provided, as in any garden, to support the plants since they are essentially being grown in containers above the ground. You also need to pay attention to the chemistry of the nutrient mix as the plant grows so you need to measure the EC and pH of the nutrient mix on at least a weekly basis to make sure the plants are being fed properly. This can be done with small digital meters that you can find inexpensively on Amazon.
Which crops seem to grow best and which are challenging?
I have not found a vegetable so far that I have not been able to grow hydroponically and have it grow really well. One issue I haven’t mentioned is the roots of the plant growing into the recirculating system and blocking the proper drainage of the system. This has been the biggest problem with cucumbers and beans which seem to have very aggressive root growth. It’s much less of a problem with tomatoes, eggplants, and peppers where the root growth is more isolated to the container so that the roots in the container look more like a rootbound pot rather than having the roots growing out the pipes wherever the nutrient solution leads them. Some people are under the impression that the flavor of hydroponic vegetables is somehow compromised by not having a “micro-biome” in the soil producing some of the nutrients that the plant uses. Boron is boron is boron. I haven’t noticed any difference in the flavors of our hydroponically grown vegetables. I think the flavor is in the genes and not in the source of the plant’s nutrients. I would love to grow the same variety of say, tomato, both in soil and hydroponically and do a side by side taste comparison. I don’t think I’ve had any bigger problems with the usual airborne pests and diseases than that of soil grown plants, although I haven’t noticed any advantage either!
What tips do you have for someone who is curious about hydroponics?
Start out with one plant. With two buckets, a small pump, a controller, and some tubing you can build a simple ebb and flow system that will work well. YouTube, the internet in general, and many books can get you started with simple designs. I can certainly help people who want to get started by providing them with help in building a system by pointing them to appropriate sources. Unfortunately, simple complete kits to build a starter system do not seem to be found. That is a hole I am trying to fill by supplying the beginner, or the person who just wants a few pots, with a complete system that they can assemble. Until then, all of the components for a system can be found on Amazon, at Home Depot, or through the many hydroponic suppliers found online. Start out by purchasing the nutrient solutions. I really recommend General Hydroponics Flora series as a good start that can be found on Amazon. If you start growing a lot of plants or just become interested it is a fairly simple matter to buy the nutrients as salts and mix your own nutrient solutions. All of the components can be purchased online. A great guide to doing this is through the use of HydroBuddy, a free nutrient calculator that will tell you exactly how much of each nutrient salt to add to the mix. It has a library of nutrient mixes for various plants.
By Jon Traunfeld, Extension Specialist; all photos by Jon Traunfeld