'The disadvantage of selling hydroponics equipment is that everyone thinks that everyone buying this equipment is growing pot," says Bill Tall, owner of City Farmers Nursery. On Saturday, December 3, City Farmers Nursery is offering a course on growing tomatoes and basil in the winter using methods of hydroponics. "Hydroponics is accelerated gardening," says Tall. "Plants grow 30 percent to 50 percent quicker because the roots don't have to fight the soil for food. You have more control over plant material and if you were to grow indoors you could control the amount of light, the type of light, and the amount of fertilizer and water [the plant] gets."
Proponents of hydroponics insist that growing plants in soil hinders their growth. Soil can harbor pests, weeds, and bacteria that can be harmful to vegetation. "The best method would be to start with a small plant. Wash all the dirt off the roots, and plant it in a non-soil growing medium like perlite, rockwool, or a popular material called hydrocorn," advises Tall. "Perlite is made out of rocks that have been heated up and popped like popcorn. Rockwool is a rock that's heated and spun, and [hydrocorn] is little clay pebbles that have been fired and made so that they're porous. None of these are organic, they are natural materials -- organic will decompose. All these materials do is support the plant; they provide nothing else."
Simplyhydro.com lists seven kinds of hydroponic systems, the most high-tech of which is the aeroponic system. In this type of system, "The roots hang in the air and are misted with nutrient solution. The mistings are usually done every few minutes. Because the roots are exposed to the air...[they] will dry out rapidly if the misting cycles are interrupted."
According to the site, the simplest type of hydroponic system is the wick system, in which "the nutrient solution is drawn into the growing medium from the reservoir with a wick." Growing mediums like perlite are recommended. "The biggest drawback of this system is that plants that are large or use large amounts of water may use up the nutrient solution faster than the wick(s) can supply it."
The system most popular with teachers is the water culture system. To get started on this easy-to-create-in-the-classroom system one would need a watertight container, like an aquarium. "The platform that holds the plants is usually made of Styrofoam and floats directly on the nutrient solution. An air pump supplies air to the air stone that bubbles the nutrient solution and supplies oxygen to the roots of the plants." This system is perfect for leaf-lettuce, or "fast-growing, water-loving plants." In fact, very few plants other than lettuce will do well in this type of system.
"You can grow a plant without anything around the root, just in water, as long as there's the proper balance of oxygen, water, and nutrients getting into the root system," said Tall. "With the flood-and-drain system, you soak the roots in water for a period of time and drain it all away for a period of time and then resoak." There are some plants that are not suited for hydroponics. "One crop you can't grow indoors is root crops [such as potatoes or carrots]."
Tall believes hydroponically grown fruits and veggies taste better "because they don't have to struggle to get the nutrients. Fertilizers are basically three main ingredients: nitrogen, which promotes new growth; phosphorus, which promotes flowers and fruiting; and potassium, which promotes root growth."
Tall explains that when growing basil, one would choose a fertilizer that contains more nitrogen than phosphorus. Tomatoes require more nitrogen in the first stage of growth. When flowering is desired, adding phosphorus and changing the light source will result in blooms within a week. "Lighting, fertilizer, and temperature. That's how you tell a plant what to do, and they're pretty responsive." Warm lighting encourages flowering, and cooler lighting is ideal for leafing and rooting.
"The initial setup is expensive," Tall says. "To grow a couple of small tomato plants...for a small setup it would be about 400 or 500 dollars' worth of equipment. But the equipment will last you a long time." -- Barbarella
Hydroponics Class: How to Grow Tomatoes and Basil in the Winter Saturday, December 3 1 p.m. to 3 p.m.
City Farmers Nursery 4832 Home Avenue (cross street Euclid)
City Heights Cost: Free Info: 619-284-6358