Easy hydroponics or soil-less gardening is a perfect utilization of rooftops, patios or yards with poor soil quality. Hydroponic gardening provides essential nutrients quickly to the roots on a very consistent basis resulting in better growth and higher yields. Hydroponics provides a more stable soil fertility, temperature, and moisture than gardening with traditional soil. Because of the ample nutrients available, plantings can be denser. Soil-less gardening greatly reduces the majority of soil born insects and diseases, reducing the need for pesticides. Easy hydroponic gardening uses less water per square foot, compared to gardening with traditional soil. Hydroponic gardening helps to eliminate the back breaking work of carrying bags and bags of soil or the endless job of hoeing weeds.
This article shares with you three different easy hydroponic systems. In these passive floating systems, no water circulating pumps, aeration pumps or engineering skills are required. Pumps are common in commercial systems. The passive floating hydroponic gardening system holds the plants just on top of the nutrient solution in cups with drainage holes, supported by a sheet of Styrofoam™™. I will first share with you Passive Hydroponic Universal Instructions that will help you get started. These instructions include: selecting crops, choosing containers, starting plants indoors, mixing fertilizer solutions, and starting plants in hydroponic solution. I will then describe the materials needed to construct three different systems including: plastic tote, wading pool, and wood frame systems.
Easy Hydroponics: Passive Universal Instructions**
Caution Even a small amount of water can be a possible drowning hazard for children. Please make certain that your hydroponic system is well protected from small children.
Cool season plants love this passive hydroponic system. I recommend a spring and fall planting of leafy green vegetables that include: lettuce (bibb, Boston, leaf, and Romaine), mustard greens, bok choy, mint, chives, and kale. Warm season crops that can be planted after the early spring crop is done include: Swiss chard, basil, cucumbers, watercress, and zinnia, an annual flower.
This article guides you through building three different passive floating gardens. The sizes include: a 6.25-gallon tote, a kiddie 4-5′ wading pool, and a 4’ x 8’ plastic lined wooden structure. Any noncorrosive container can be used, including water tanks, buckets, or tubs that hold water and are 4 to 6 inches deep. To hold the plant roots just at the surface of the solution you will need net pots or Styrofoam™ coffee cups. Net pots can be purchase from a commercial hydroponic supplier.
Cut cup holes in a 1½” thick Styrofoam™ sheet large enough to allow the net pots or cups to drop 1/8 inch below the bottom. A 3” net pot or a standard Styrofoam™ cup will need a 2½” hole. A 2” net pot will require a 1¾” hole. . Standard Styrofoam™ cups need to have 1/4″ slits cut in the sides and the bottom to let the roots grow through.
Purchasing seedling transplants is the easiest way for beginners to get started. It is easy to find a large selection of low cost, green leafy vegetable varieties in any garden center. In most cases the seedlings have been started in a soil-less mixture. It is common for these garden centers to have the plants displayed outside so they are already acclimated to the outdoor environment.
Starting Plants from Seed Indoors
I have had great success starting plants in compressed peat pellets (Jiffy-7). The pellets are very easy to water and show good resistance to dampening off disease. Start the seeds approximately three weeks prior to moving them outside. The plants need to be fully rooted with leaves approximately 1 to 1 and 1/2” inches long before moving them outdoors. It is critical that you harden off your plants before setting them out. Hardening off is the process of slowly acclimating plants to a more sunny, cool, windy outdoor environment. A week before transplanting, place your plants outside in a shaded area for approximately an hour. Then extend the time one hour each day and place in more direct sunlight each day for the remaining part of the week. Hardening off will have a very positive effect on the success rate of your transplants.
Mixing Fertilizer Solutions
Add 1 to 2 level teaspoons of water-soluble 20–20–20 or 18-18 -21 fertilizer with micronutrients to each gallon of water (J. R. Petters inc. All Purpose 20-20-20 Water Soluble Fertilizer, or Miracle-Gro® Water Soluble Tomato Plant Food 18-18-21) and ½ to 1 teaspoon of Epsom salts (magnesium sulfate). See figure 2. Additional calcium may need to be added if you have soft water. Stir until dissolved. In most cases you can grow an entire crop of greens without changing or adding solution. Monitor the water level and add water if it becomes low. If it rains alot you may need to add additional fertilizer and Epsom salts at the same ratio to compensate for the additional volume of water. The pH level of the solution should be checked with a simple pH tester that can be purchased at a pool supply store or garden center. The final pH of the solution should be 5.5 to 6.5. Adjustments can be made upward by adding agricultural line. By adding aluminum sulfate, you can lower the pH. You can grow two crops of greens in the same solution before the entire solution needs to be changed.
Starting Plants in Passive Hydroponic System
Transplants should be flat bottomed, fully rooted in a soil-less media consisting of: rockwool, foam cubes, or compressed peat pellets. I would not recommend coconut fiber, sand, Perlite, or Vermiculite, because it doesn’t form a ball, which makes it more difficult to transplant. A flat bottom seedling makes good contact with the solution in the bottom of the cup. Do not add, remove, or pack the soil-less mix in the cups. This soil-less root ball should be surrounded by air. By having the roots extend slightly out of the nutrients the plant can absorb needed oxygen through the exposed roots. Use a toothpick can be used to prop the plant so it stays upright in the cup. It is important to remember that the plants roots should not be covered by the solution. Do not place the cup deeper than 1/8” into the solution. If the plant’s roots seem too wet, place the cup on its side to reduce contact of the solution.
Easy Hydroponics: Tote with Styrofoam™
This easy hydroponic system is low cost, easy to build and easy to operate. It’s an excellent way to explore soil-less gardening for the beginner. This is a reliable system I used with classroom
4-H clubs to encourage participation in the gardening program. I’m not aware of any of the demonstrations that were not successful. You can build this hydroponic system for less than $10. I have added two larger hydroponic systems below that you may want to try after you have success with this easy hydroponic passive tote system.