Doc Hydro,
    My plants develop burned areas and splotches on the older leaves.
    The new leaves look fine. Are they deficient in something or what could be the problem?

“With todays hydroponic systems, growing mediums and fertilizers, you should never see nutritional deficiencies. Unless you have some weird fertilizer designed for blueberries, or an old bag of soil amendment meant to be used under your landscape plantings all of the products available from our store have a complete blend of nutrients needed for optimal plant growth. All of our grow medium has been tested time and time again to produce lush growth. Leaf changes often occur as a result of pH problems (often a week or two prior to you noticing symptoms). A rise or fall of pH above or below beneficial levels produces an environment where certain elements are unavailable. Many deficiencies look very similar with pale areas showing up on the leaf margins, between the veins, or in multiple sites. I recommend that you maintain the proper pH by testing your nutrient solution regularly (daily if possible), test your soil pH often, use high-quality nutrients adjusted to the correct pH. Stay away from bagged soils from home stores unless you are sure of the quality. Stay away from single nutrient supplements unless you are sure how to use them (Epson salts for example), and never over or under fertilize. If you correct the pH problem all of your new growth and future growth should be fine. We never worry if the older leaves have a few spots as the plant tends to discard these over time anyway.”

Doc Hydro, what light should I get?

“That’s a tough question unless I know the size of the area you want to light and whether it will be used for low light or high light plants. Low light plants like lettuce, most houseplants, orchids, plant seedlings and cuttings do well with compact fluorescents or T5 fluorescents. We discourage regular fluorescents unless the bulbs are brand new, cool white and are changed every few months. The plants listed above will thrive under these low energy light sources and you will save on electricity. It is also hard or impossible to burn plants with these light sources. High light plants such as tomatoes, peppers, certain palms, garden and landscape plants which require full sun and other plants that can tolerate intense light need HID lighting. High Intensity Discharge Lighting (HID) provides large amounts of light by passing a regulated amount of electricity through a sealed envelope of a metal vapor gas rather than through a filament. They easily out produce filament or fluorescent lights and give the most light per watt of electricity used. The gas components can be changed to give off a certain spectrum of light, for example, mostly blue or mostly red. These bulbs need a ballast to strike and maintain the light emitting arc and to regulate the amount of electricity flowing to the bulb. You should also use a good reflector that can concentrate and aim the light in a certain direction (usually down to your plants). In our store we use mostly high pressure sodium although switchable ballasts and the new electronic ballasts can burn either metal halide or high pressure sodium bulbs depending on whether you need blue or red light. We recommend a 150 to 250 watt light for a 2’ x 2’ area, a 400 watt light for a 2’ x 4’ area, a 600 watt light for a 3’ x 3’ area and a 1000 watt light for a 4’ x 4’ or 5’ x 5’ area.”

Doc Hydro, why is hydroponic equipment so expensive?

“Think of hydroponic gardening as a hobby. Now think of some hobbies like scuba diving, motorcycle or atv riding, kayaking, collecting firearms or coins. Sometimes hobbies just cost money but we get something out of them, some enjoyment or product or even appreciation that compensates for the expense. Hydroponic equipment is designed for one purpose only, has a somewhat limited base of participants and often requires expensive inputs in the way of raw materials such as copper, plastics and fertilizers made from petroleum and shipping costs (a 1000 Watt ballast weighs 40 lbs. and is mostly copper or aluminum). In my garden, where only the best will do, I spend $.50-$1.00 per watermelon seed and I plant at least 200 a year. My other seeds like tomato and peppers run about $2-$4 for 10 seeds. Add all of the time inputs, plastic sheeting for weed control, row covers, drip systems, timers, soil amendment etc. and it really adds up. Is it worth it? You bet it is. Also, hydroponic equipment lasts a long time and is readily resalable when you are done with it. And if you are a Hydroponics Club member and shop with us you can save up to 80%. Now it’s not so expensive.”

Doc Hydro, how do you recommend that I get into commercial hydroponics?

“It certainly helps to have a background in chemistry, plant science, agriculture, business and microbiology because these fields are so helpful and are used in commercial hydroponics. You can also be a handy person, with great drive and perhaps have a green thumb without all of the education and do well. I would start small and if you decide it is for you find a crop that is always in demand in your area at a premium price, can be produced hydroponically, and is a plant that you really enjoy (for example Gerbera Daisy’s, Roses, Tomatoes). Then it is no longer a job, it is fun! If you can find a hydroponic producer that you can apprentice with, you will learn more in a few weeks than you can in months on your own. Good luck!”

Doc Hydro, what is better, ebb and flow, soil or aeroponics?

“Aeroponics (there is little or no growing medium and nutrient solution is sprayed around and on the roots continuously) requires a somewhat steep learning curve but it can be done by someone dedicated and has the time to provide constant attention. For example, pH swings are common and if your pump or electricity goes out you plants could be in deep trouble. Plants grow VERY FAST in an aeroponic system. Soil growing is very easy. Pick a good soil, pick a fairly roomy pot and hand water. If you add myccorhizae to the soil you can also avoid dramatic changes in soil pH. It couldn’t be easier unless you forget to water. The ebb and flow system (nutrient is pumped to stand several inches in a tray then drained) is also very easy and is great for those of us who like to take short vacations. Your timer takes care of all the watering and you check your nutrient solution in the reservoir every few days and maintain the correct pH. You will replace the nutrient solution every 1-2 weeks. The pots can be somewhat smaller in this system and it is intermediate in how fast your plants grow. I list them in this order: Easy-soil, somewhat easy-ebb and flow, somewhat difficult-aeroponics.