HYDROPONICS? YES!!

** GARDENING HYDROPONICALLY THE SQUARE FOOT WAY IS HERE **

(Another innovative idea from Mel's fertile mind!) 

     While filming one of our PBS-TV Shows at Disney World in Orlando , Florida , we were invited to tour and subsequently film several shows at the Land Pavilion where they were exhibiting several new methods of growing vegetables – some even suited for the moon! One demonstration was the standard hydroponic method where plants are grown, not in dirt or soil, but in water.

     Another method (but this is for another time) was airoponics where the roots hung down in a closed, lightless area where they were sprayed with a fine water spray and the plant top grew up a string in the sunlight - very similar to our SFG vertical method.

     But - back at the ranch. At the hydroponic display, they had large shallow pools of water with 4’x8’ sheets of Styrofoam floating on the surface. The actual plants were started in little cups filled with a soil mix much like Mel’s Mix. Holes were drilled at uniform spacing in the Styrofoam and the cups fit tightly into those holes. When the seeds sprouted the roots grew down right into the water.

     Apparently a plant can have two kinds of roots - normal air roots for growing in soil and also water roots. Remember, the SFG book tells you how the roots do not actually grow in the soil particles, but meander their way through the air spaces between those particles. In addition, a plant has the ability to grow a slightly different type of root that will grow in nothing but water. The water roots can take up the oxygen and nutrients in the water solution and, believe it or not, provide the plant with all the energy it needs. Liquid fertilizer was being added to the water which was continuously circulated to keep it fresh and moving. The top of the plant had plenty of room to spread out on the Styrofoam surface just as if it were planted in a garden. If it was a vine crop and hanging support strings were provided, the plant would just climb up the string or could be attached to it very easily by gently twisting it around the string once or twice a week.

     I was so amazed and enthralled with this method, that when we came home I decided to see if we could make Square Foot Gardening do the hydroponic thing. After all, the only thing needed is a pool of water which could be provided with our standard 6 inch deep 4 ft by 4 ft box with a plywood bottom and lined with heavy duty six-mil plastic so the box doesn’t leak. It would be just like a square 6-inch deep wading pool. The box could sit on the ground in the garden, patio, or even the deck. Or it could be raised up to sit on a tabletop, sawhorses or even on legs made out of wood or stacks of cement blocks. There is no end to the location and setting. And for the surface, I thought, why not cut out twelve inch by twelve inch pieces of half to one inch thick Styrofoam and cut holes at either the one, four, nine, or sixteen spacing, the standard spacing for Square Foot Gardening. After building a sample box, I set it on sawhorses out in the yard to get maximum sunlight. Having it up higher meant no bending over to garden.

The 4 ft by 4 ft box with a plywood bottom, no holes for drainage, set up on two saw horses. Notice the vertical pipe legs which will become the vertical frame for the vine crops to grow on.

    Next, I added the plastic liner, filled it with water, let the sun warm the water and then added the Square Foot Styrofoam pieces. It looked great - so far so good!

Notice the clear plastic has been installed as a lining and the box filled with water. Rather than using thin sheets of 12 inch by 12 inch Styrofoam I started by floating standard commercial seed starter boxes in the water. This worked so well as the plant roots grew down into the water that I later started using the square foot Styrofoam as explained in the above article.

     I first experimented with standard commercial Styrofoam seedling boxes I had which were a no-work start to the experiment. They just floated in the water and the seeds were planted in the individual cells which I filled with Mel’s Mix. That stuff works everywhere and for every purpose. (Make sure you have some extra mix around for other purposes later after you make the mix for your regular Square Foot Garden .

     Later, I had obtained some standard small cups at the deli and made sure the cups fit tightly in the holes I cut in the flat Styrofoam 12"x12" squares. Then I planted some seeds and some transplanted seedlings. I planted each square foot with a different crop until the entire 4x4 was filled with a variety of lettuces, beets, Swiss chard, scallions, peppers, radishes, and spinach. I located the other trial hydroponic box in a patio space out in full sun so it made a very interesting addition. As I sat there watching the plants grow, I thought of all the different possibilities.

     One idea I thought of was to leave one or two of the Styrofoam squares empty and to plant water lilies in that square. They are usually grown in a clay flower pot in soil and then just set down in the water so everything except the leaves are below the water surface. Of course, another idea would be to put in a water fountain that would create a miniature garden landscape. Disney never thought of these things. Their ideas were to try out ways that would be adaptable in many locations around the world and perhaps even in space.

     Now one problem came to mind. If we had an open-water surface out in the garden, what would be sure to find it? Mosquitoes lay their eggs in water and the nymph grows in that water. Surely mosquitoes would find this pool of water and find it a charming place to lay their eggs (which, by the way, look like little black rafts - the eggs are glued together turned straight up). Once they hatch, the larvae go to the bottom of the water to look for food. As they develop and grow larger they then turn into the next stage of development where they must wiggle to the surface and poke their tubes through the water surface to breathe air.

     The well-known treatment for standing water is to cover the surface with a very thin film of oil that makes the surface tension so tough that the larvae cannot poke through it; thus they suffocate by not being able to breathe any air. However, there is another unique way to get rid of the mosquito larvae and that is to introduce something that will eat them. That would be - a little drum roll please – FISH. So, I could have cute little tropical fish swimming around beneath my plants, eating all the mosquito larvae and getting large enough to go into my indoor aquarium for the winter. What do you think of that idea?

     But how would the SFG plants get their nutrients? Fertilizers come in both organic and chemical forms as well as dry powders or liquids and for this operation it was easiest to add a liquid to the 4x4 box of water. This could be done, perhaps, on a weekly basis, but as I experimented more and more I found that unless you were after very vigorous and rapid growth, the plants seemed to do quite well in just plain water. Hence we could have an Organic Hydroponic Garden . Who else on your block could say that?

     Another idea was to attach a SFG vertical frame and grow vine crops. It was very easy to install the typical SFG vertical frame as described in my book. I made it out of the same electrical metal conduit but instead of driving steel rods into the ground to hold up the pipe legs, I used metal clamps that held the legs tightly to the outside of the box yet in an upright position as seen in the first photo. Or, four legs could even be placed, one in each inside corner of the box resting on the inside bottom. I could envision an entire arbor placed over the hydroponic box and planting vine crops all around the outer 4 sides with shade crops in the interior squares.

     The next idea would be to take this whole contraption indoors and grow under lights in the basement or on an enclosed porch all winter. If necessary, we could add an aquarium tank water heater because it was obvious the plants would grow quicker and better the warmer the water was up to a point of about 80 ° F. That worked also, so there seemed to be no limit to this idea, only the imagination of the grower. Did we grow more this way than in a conventional SFG outside? No!  Could we grow things that we could not grow in a regular SFG? No!    Did we have a lot of fun? Yes!

     In fact, this would make a particularly challenging science project for a student of any age. I hope you’ll give it a try and send us pictures and share your experiences.

     You might ask what made me think of all this hydroponic growing and experimenting I did 20 years ago. I was recently screening all of our original PBS-TV shows in order to reproduce them and issue DVD’s of some of the most interesting and still pertinent episodes.

     There were several trips we made to Florida and Disney World was in several of them. We also did segments on their behind-the-scenes planting, growing and shearing of all their hanging baskets, topiary figures, as well as several parts of the Land pavilion. Another interesting area we filmed was a tour through all the different country’s gardens at the Epcot Center . (Watch our catalog page to see when we have those DVDs as products you can order.)

     Next question – are we going to design, build and sell a SFG Hydroponic kit with all the parts I mentioned above? Yes, if we get enough interest. Let us know with an e-mail – or just go build one yourself and give it a try. It’s a lot of fun. And, don’t forget those guppies and swordtails.