There are really just a few things you need to consider when just starting out. Plant nutrition (nutrients/fertilizers), lighting, pH level, type of system, temp (both the top, and root zone), humidity and whether your plants are compatible with your conditions. Plants are quite tolerant of most varying conditions. So will your plants die if one changes a little? No, not at all. Sure they will do better under the perfect conditions, but the change would need to be quite severe for the plants to die. Everyone wants the prefect plant, but just like with soil grown plants there are varying conditions that will affect how well the plants will do, but the plants will adjust as best as they can.
The type of system doesn’t matter too much, most plants will do fine in all of them. Although you should design your hydroponic systems with your plants in mind. Taking into consideration where it will be placed, how big the plants will get and easy maintenance. The air temp should be taken into consideration, finding out what type of climate they like and try to mimic that. If growing outside, pick plants that grow well for your season. Most plants will do well in a large range of humidity conditions, but high humidity and not enough airflow around the plants could result in the plant getting diseases.
Nutrients/Fertilizers
In any type of hydroponic system, all the micro and macro (simple way of saying major and miner) nutrients the plants need for growth must be supplied through a hydroponic nutrient solution. This is the fundamental principal of hydroponics (growing without soil), because with soil grown plants they would get these nutrients directly from the soil. Carbon, hydrogen and oxygen are absorbed from the air and water. The macro nutrients are those needed in relatively large amounts, they include, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S). Micronutrients (or trace elements) include, iron (Fe), manganese (Mn), boron (B), molybdenum (Mo), zinc (Zn), copper (Cu), and chlorine (Cl). These are used in very small amounts by plants, that’s why their referred to as “micronutrients.”
What makes all this easy, is that all the elements needed for successful hydroponic growing are available pre-mixed from, and from many different hydroponic supply companies. So in other words, you simply don’t need to worry about all of that chemistry. New hydroponic gardeners should simply use these commercially available mixes, rather than trying to prepare and figure out their own nutrient solutions. These pre-mixed formulas come in three general forms, Grow formula, Bloom formula and Continuously flowering/fruiting plant formulas.
“Grow” formulas are for the vegetative stages (foliage, not flowers), “bloom” formulas are for the flowering stage (when they begin to flower), and “continuously flowering/fruiting” formulas are for plants that do both at the same time like strawberry’s, tomato’s and peppers. Just make sure the nutrients you are using are for hydroponics, and not soil. Soil nutrients wont have all the micronutrients you need in it. Nutrient temp is often overlooked but it’s important, just get a small inexpensive fish tank thermometer and check it regularly. You want it to be between 65 and 72 degrees to mimic the root zone in there natural (soil) environment.
pH Testing Simplified
Controlling pH is simple, pH testing kits can be bought for as little as $8 in the form of pH drops. Using the drops is more advisable for the beginner, as compared to buying a pH test meter. It’s much less expensive, but also you don’t need to worry about calibrating it to get accurate results. Learning to read the color is easy, and because you don’t need to be at an exact pH like 6.8 all the time, but rather within a range like 6 to 7 the drops will do just fine.
Now that you know what the pH is at, getting it in the right range is easy using pH adjusters. pH adjusters come in two forms (liquids, and dry powders). Both come in “pH up” and “pH down.” There is a little learning curve to learning how much to add, but this is quick and easy to learn. If the pH tested to low, just add a small amount of pH up until it’s in the right range. If it tested to high, just add a little pH down until it’s in the right range. You should test the pH every couple of days, so you know it will always be in the right range. Most all plants will do good at around 6, or within a range of 5.5 to 6.5.
Lighting
The subject of artificial light, or grow lights can get complicated, and everyone seems to have different opinions and preferences. There are a wide variety of artificial lighting options to choose from, making it even more difficult. Metal Halide (MH), High Pressure Sodium (HPS), LED Grow Lights, High Output Fluorescent, as well as Compact Fluorescent lights (CFL’s). There are also what are claimed to be all spectrum bulbs, they claim to have all the spectrum’s of the suns light in one bulb.
But the last form of light is often forgotten about, it’s simply natural light (the sun), this is my favorite. Natural light truly has all the spectrums of the suns light, and with the right intensity. Best of all, no need for expensive lighting equipment because natural light is free to everyone. But for those who still want to use artificial light, I’ll try to break it down to simplify them.
- Metal Halide Bulbs emulate bright summer sunlight, and are probably the most commonly used. They focus on the blue end of the spectrum, but give good results and most all plants will do well with Metal Halide Bulbs. They do get hot, so they need to be well ventilated and spaced so they don’t burn the plants.
- High Pressure Sodium Bulbs are the only grow lights comparable to metal halide bulbs. They focus more on the red end of the spectrum. This is the type of light fruiting and flowering plants like best. Because of the focus on red light, some varieties of plants grown with sodium lights alone can become elongated and leggy because they need more light from the blue end of the spectrum than the sodium lights provide.
- LED Grow Lights are the newest to the market in hydroponics, thus probably more expensive. They use about 1/4 the electricity, and don’t produce a lot of heat like the Halide and Sodium Bulbs do. Vegetative growth is a little slower compared to a 400 watt HPS and fruiting and flowering is slightly slower also, but healthy and strong. LED lights come in different spectrum’s (blue, red) also. Both spectrum’s should provide the best results.
- High Output Fluorescent’s like T5’s and T8’s produce very little heat which lets you position them closer to your plants to raise the light levels. T5 high output fluorescent’s put out 5000 lumens per tube (at the bulb). The lumens levels drop quicker with fluorescent the farther away the plants are than they would with Halide or sodium lights.
- Compact Fluorescent lights (CFL’s) these do not produce much heat or use much electricity either. CFL’s have the ballast inside the bulb instead of in the light fixture, making them small and compact. These come in two spectrums 6500K and the 2700K. The 2700K warm bulb tends to work best for most plants. CFL’s don’t put out a lot of lumens (their intensity), thus you will need to use many in close quarters of each other, and for plants taller than a foot, regular fluorescent tubes can be supplemented on the plant sides because the light wont penetrate the foliage very far. CFL’s tend to work best for small plants, seedlings and for low light requiring plants like lettuce.
